albuquerque

__**Albuquerque Reach Restoration Project**__


 * Introduction**

The Albuquerque reach of the Rio Grande river plays and important role in the form and function of the river system as a whole. The presence of the large Albuquerque metropolitan area in this reach has strongly impacted the hydrology and geomorphology of the river throughout time. The influence of the man-made changes to the Rio Grande in this reach of the river have adversely affected the two existing endangered species, the Rio Grande Silvery Minnow and the Southwestern Willow Flycatcher. As a result, restoration efforts are needed in order to meet the sustainability needs of these species.

We begin this report by characterizing the historical and current hydrology and geomorphology of the Albuquerque reach in order to provide a context for possible restoration efforts aimed at the remediation of habitat for the Rio Grande Silvery Minnow and Southwestern Willow Flycatcher. The life histories and sustainability needs of these two species will be described in order to identify important restoration needs. The current hydrological and geomorphological constraints on these restoration needs will be given in order to provide a realistic basis for restoration project design. Finally, restoration efforts that may be successful under these constraints will be outlined.

__Physical Location, Climate, and Historical River Constraints__
The Albuquerque Reach of the Rio Grande is typically defined as the 40-mile stretch of river between Angostura Diversion Dam north of Bernalillo and Isleta Diversion Dam south of Albuquerque. This section of the river makes up one quarter of what is known as the Middle Rio Grande (MRG). It is by far the most urbanized portion of the MRG with the cities of Albuquerque and Rio Rancho within these limits. Ecosystems and topography draining directly to this reach of the river vary greatly with a riparian corridor running along the banks of the river, upland grassland and shrubland, and finally mountain forests approximately 5,000 feet above river elevation. The variability in topography produces considerable differences in climate from one location to another.

The Albuquerque Reach is located in an area with a semi-arid to arid climate; however, precipitation patterns can differ substantially on a local scale. At the lower elevations and on the mesa west of the Rio Grande, precipitation totals are lower while temperatures are greater than those recorded at higher elevations. Rainfall totals at the Albuquerque Sunport average about 9 inches per year with the majority of precipitation occurring during convective summer storms associated with the North American Monsoon (WRRC 23050). Annual snowfall totals are approximately 10 inches as well. Meanwhile, precipitation amounts at higher elevations such as Sandia Crest are considerably greater due to orographic effects. In comparison to the valley and West Mesa, Sandia Crest averages approximately 23 inches of rain and 115 inches of snow per year (WRCC 298011). In addition to the Sandia and Manzanita Mountains to the east, the Jemez River enters the Rio Grande just south of Angostura Diversion Dam. This water arrives from the Jemez Mountains and Valles Caldera, both areas of higher elevation as well. Local precipitation is of most significance during short duration summer storms that can provide large amounts of runoff for the Rio Grande. However, the fact that these events come and go quickly means that the pulses felt in the river follow the same pattern. Therefore it is important to keep in mind that flows generated within the Albuquerque Reach are most often of minor significance to those entering the reach from above in terms of total volume of water and duration.

The river has and always will be constrained by the hydrologic inputs to the larger system or more specifically the climate of the headwaters and higher elevations of the Rio Grande Basin. The natural flow regime of the Rio Grande can be summarized as inputs from the headwaters area of Colorado’s San Juan Mountains, major tributary in the form of the Rio Chama and Jemez River, and finally more local minor tributaries, with the proportions approximately 60-65, 20, and 10-15 percent of total flow volume, respectively (Llewellyn and Vaddey, 2013). As discussed previously, those local contributions although significant at a short timescale are small compared to the melting snowpack. Ultimately, the water supplied from higher portions of the basin defines the hydrology of the Albuquerque Reach, especially during important ecological times of the year. Annual differences in snowpack totals and melting of the snowpack will lead to different annual discharges and timing of flows through the system. Figure 1 shows hydrographs from three different years, demonstrating the drastic differences in flow patterns, timing of flows, and total volume of water.



Important constraints within the current hydrologic landscape are the spatial and temporal variations in flow through the reach. Poff et al. (1997) suggested five key temporal changes in flow patterns: magnitude, frequency, duration, timing, and rate of change. Magnitude relates to the amount of flow per unit time, frequency is the recurrence period for a given flow event, duration is the length of an event, timing is the regularity in occurrence of a flow, and rate of change deals with how quickly a flow changes from discharge to another. These different characteristics of river flow will have impacts on the geomorphic and biological characteristics of the Rio Grande and are important to keep in mind when making decisions for restoration efforts. Snowmelt will produce flow patterns with long durations, reliable timing, and low rates of change. Conversely, monsoon storms typical of the mid-to-late summer months in Albuquerque produce flows defined by considerable flashiness, otherwise known as a high rate of change in flow. In addition, the storms can produce flows of large magnitude, although the duration is likely to be short lived.

The Rio Grande has long been subject to climatic and anthropogenic impacts. The climate within the Rio Grande Basin has fluctuated greatly between wet periods and times of drought. Even prior to the arrival of the railroad in the American West, there are reports of the river running dry during summer months (Phillips et al., 2011). Therefore, restoration goals must realize that the geomorphic and ecological systems of the Rio Grande were likely adapted to extremely variable events. In addition to climactic fluctuations, the river has long been subjected to anthropogenic use, most notably in the form of irrigation for crops. It is thought that early diversions by native people and even the construction of acequias had little impact on the river system. However, with the addition of large-scale farming in the San Luis Valley of Colorado, the construction of dams on the Rio Chama, and construction of infrastructure to control flows to protect increasing populations, the discharges entering the Albuquerque Reach have been greatly altered.

__Current Reach Hydrology__
//Water Use and Infrastructure//

With the possible exception of future climate change, anthropogenic use of river water is currently the dominant constraint on flow in the Rio Grande. Diversion of river water for the Albuquerque Reach begins at Angostura Diversion Dam, which is the northern boundary for this specific reach. The diversion dam has the capacity to divert 650 cubic feet per second (cfs), however that total is likely significant lower at most times due to the total discharge within the river. Because of the historical importance of agriculture within the valley of the Albuquerque Reach, a series of canals, drains, and acequias have been constructed throughout the valley and are managed by the Middle Rio Grande Conservancy District (MRGCD). Figure 2 shows a schematic of the irrigation system set up within the Albuquerque Reach. The MRGCD irrigation season lasts from March 1st through October 31st each year with diversions dependent on the amount of water available during the season. Part of this water comes from the San Juan-Chama Diversion. The San Juan-Chama Diversion was completed in 1971 and provides an average of 96,200 acre-feet per year and 1.35 million acre-feet over a 10-year period. Almost half of this water is allotted for the city of Albuquerque’s drinking water supply while another large portion goes to the MRGCD. Although this water is not part of the natural flow of the river and is completely allocated, it may prove to be the most reliable source of water coming into the basin and could possibly be used for beneficial purposes as well. In addition to surface water diversions, ground water wells are located throughout the reach. These diversions will greatly affect the hydrology of the river and aquifers are clearly connected to surface flows.



While the physical removal of water from the river is likely most significant to the system, manipulation of the flows is also important to consider. Cochiti Dam is the most significant control on discharge, altering flows through the Albuquerque Reach since 1973. Cochiti Dam was built to reduce flooding damages to the city of Albuquerque and has reduced the probability of extremely high discharges. A flow of approximately 11,500 cfs used to have a return period of approximately 10 years. Since the construction of Cochiti Dam, the flood event with a 10% chance of occurring in any given year is about 7,900 cfs. Flow coming out of Cochiti Dam is limited to the designated safe channel capacity of 7,000 cfs (BOR, 2012). Theoretically, if flow comes into Cochiti Reservoir at a level below 7,000 cfs, the same amount will be released from the dam. However, when flows come into Cochiti Reservoir above 7,000 cfs, the release will be limited to that channel capacity flow as occurred in 2005 (BOR, 2012). Impacts of Cochiti Dam on flow durations and peak flows at the Central Avenue gauge can be seen in Figures 3 and 4. A second control on flows through the Albuquerque Reach is designated by the United States Fish and Wildlife Service, which requires 100 cfs at the Central Avenue gauge in Albuquerque for the purpose of RGSM habitat (BOR, 2012). Although this is meant to be a standard that won’t be broken, flows may drop below this level due to severe drought. For example, in 2013 flows were reduced to approximately 50 cfs at the Central Avenue gauge in order to extend the period of time that water could reach the gauge with the idea that some water is better than no water. Although water use in the Rio Grande system either created or enhanced these dry-river conditions, the adaptability of flows through the infrastructure in place is essential for future native habitat. In wetter years, water managers must also use surplus to enhance conditions, just as would have been typical of this fluctuating river.



//Water Quality//

With a large proportion of the total population of New Mexico residing within the area surrounding the Albuquerque Reach, water quality issues are likely to be most significant in this section of the Middle Rio Grande. Perhaps the most obvious inputs to the system are the storm water inputs associated with the North Diversion Channel (NDC), Calabacillas Arroyo, and the South Diversion Channel-Tijeras Arroyo. The NDC, for example, drains approximately 70 square miles and 46% of the city of Albuquerque (MRG-ARWG, 2008). Water quality sampling of arroyos began in 1992 with an agreement between the Albuquerque Metropolitan Arroyo Flood Control Authority, the City of Albuquerque, and the U.S. Geological Survey (Kelly and Romero, 2003). Although there are a large number of contaminants entering the river, fecal coliform levels, an indicator of total watershed health, are high within the Albuquerque Reach (MRG-ARWG, 2008). Some of the major contributors to these levels are avian waste, canine waste, and human sewage (Kelly and Romero, 2003). The outlet from the wastewater treatment plant also enters the river in this reach. New areas of possible concern deal with estrogenic or endocrine disrupting chemicals that are released from the treatment plant into the river and how those chemicals may impact riparian species, specifically the endangered RGSM (Buhl, 2010). However, the impacts of these chemicals are not well known at this time. Severe wildfires can also pose a threat to water quality as burn scars promote large amounts of runoff mixed with ash and sediment eroded from the burned area (Berli et al., 2008). For example, after the 2011 Las Conchas Fire in the Jemez Mountains, ash in the river caused a reduction of intake at drinking water intake structure for a number of days, meaning the city switched to groundwater to supply citizens during that time. These water quality issues are all in some way related to humans, thus, the native biota of the Albuquerque Reach are likely not adapted to these levels.

__Future Constraints__
It has been suggested that global climate change will present considerable challenges to the Middle Rio Grande. Temperatures are expected to continue to rise while the amount of water input to the system will be about the same as present day averages (Llewellyn and Vaddey, 2013). Therefore, warmer temperatures will likely lead to move evapotranspiration as well as more precipitation in the form of rain instead of snow. Because the Rio Grande is so dependent on melting snowpack to provide the baseflow for much of the year, future flows will likely be drastically changed in terms of timing, magnitude, and duration with decreases in supply for much if not all of the year (Llewellyn and Vaddey, 2013). In addition to a declining water supply and increasing temperatures, New Mexico’s population is expected to double from 2005 levels through 2060 (PEPP, 2008). It is clear from these predictions that water must be used more intelligently in this arid environment and people will need to work together to produce hydrologic conditions suitable for native ecological systems.


 * Geomorphology**

The geomorphology of the Albuquerque reach plays and important role in the ability of the Rio Grande to support its endangered species. The geomorphological conditions present in the Albuquerque reach of the Rio Grande are characterized by a complex network of man-made and natural structures and processes interacting on various spatial and temporal scales.

__Historical Geomorphology__

The historical geomorphology of the Rio Grande in the Albuquerque reach was characterized by a braided channel that continuously shifted its course across a wide floodplain. Early accounts of the river describe the presence of cottonwood stands along the river and detail many instances of overbank flooding (Scurlock, 1998). The historical Rio Grande tended towards aggradation, a process that helped to drive the movement of the river channel across a wide floodplain. The river aggraded over a period of time and then left its elevated channel in response to some hydrologic event in a process called river avulsion. This cyclical movement of the river is described as a period of dynamic equilibrium in which riparian areas became established during the river’s aggradation and then new areas for riparian recruitment were established during periods of instability, such as extreme flooding, in which the river eroded and deposited sediment as it changed its main channel location (Crawford et al., 1993).

Although some of the most dramatic human impacts to the Rio Grande occurred in the 20th century, human interactions with the Rio Grande began influencing its form and processes as early as the 14th century. Even at this early stage of settlement along the river, particularly in the Albuquerque reach, a progressive increase of irrigated agriculture began to steadily decrease the flow present in the river. The development and evolution of land-use activities in the Rio Grande watershed, such as intensive grazing and logging, also contributed to an increase in sediment deposition along the river as well. The decrease in flow coupled with an increase in sediment deposition accelerated the river’s natural tendency toward aggradation, increasing the frequency of channel movement and overbank flooding into the late 19th century (Scurlock, 1998 & Crawford et al., 1993).

Major man-made structural changes to the Rio Grande, especially in highly populated areas of the basin such as Albuquerque, dominate the story of the river throughout the 20th century. The increased frequency of flooding and river avulsion, as was discussed above, led to the destruction of settlements and irrigated agricultural areas in the late 19th and early 20th centuries (Scurlock, 1998). In response to these problems and to a need for increased water diversion development, Congress established the Middle Rio Grande Conservancy District in 1923. The district built long stretches of riverside and internal drains along the middle Rio Grande and, using the sediment dredged from the river and drains, built the first levee systems in order to constrain the river to a single channel in the 1920’s and 1930’s. The increase in water diversions and the concentration of sediment deposition in a single channel only served to further the aggradation of the channel, increasing the amount of flooding and causing many levee breaks up to the 1950’s (Graf, 1994).

In an attempt to minimize the flooding risk to the large Albuquerque metropolitan area, the U.S. Army Corps of Engineers began a process of channelizing the river through the use of jetty jacks and levees. Jetty jacks were installed along the river channel in the 1950’s in order to protect the newly strengthened levees, vegetation was cleared out of the main channel, and conveyance channels were built to divert water for various uses (Graf, 1984). Modifications to the main channel were made with the goal of moving maximum amounts of sediment in order to allow for flood protection (Thompson, 1965). These efforts contributed to the channelization of the river but did not completely control the flooding and sedimentation of the river. In response to continued flooding and levee breaches along the system, several reservoirs were constructed, as was discussed previously in the hydrology section, in the middle to late 20th century. These structures served to control flooding, store water for human uses, and retain sediment. Over the course of these activities culminating in the completion of Cochiti Dam in 1975, the Rio Grande in the Albuquerque reach became narrower and less braided with a channel tending towards degradation as opposed to the natural aggradation that had previously dominated the river’s geomorphology (Scurlock, 1998).

__Current__

The combined influence of human activities and structural changes to the Rio Grande culminated in the form and function of the river in the Albuquerque reach today.

//Cross sectional description//

The channel shape of the Rio Grande in the Albuquerque reach today has evolved as an artifact of the previously described channelization efforts. The average width of the channel today is 600 feet and follows a much straighter path, a significant change from the average width of approximately 1300 feet that serves as the baseline width for the system, measured from 1917 to 1918, before the most drastic channelization efforts began (Mussetter Engineering, 2002). Thus, the effort to channelize the river has succeeded, despite the ecological harm that this goal has wrought on the natural system dynamics of the Rio Grande.

//Bed Materials and Sediment Transport//

In order to characterize the geomorphological factors at work in the Albuquerque reach of the Rio Grande, it is important to understand some basic components of the sediment transport processes at work in the river. The analysis of sediment loading in the Rio Grande will help to determine the transport state of the river in order to establish both potential geomorphological needs for restoration and constraints on the possibilities for restoration in terms of the life cycle requirements of endangered species such as the Rio Grande Silvery Minnow and Southwestern Willow Fly Catcher.

Daily total suspended sediment discharge (tons per day), measured at the USGS gauge at Albuquerque, was considered along with the daily flow value (cfs) from 1973 to 2013. This time period represents a consistent hydrologic management of the Rio Grande due to the completion of Cochiti dam in the mid 1970’s. Based on principles of sediment transport, the relation between water discharge and sediment discharge, called a rating curve, is often modeled by a power function fitted to the data, as follows:



Where Q s is sediment discharge, a is a regression coefficient, Q is water discharge, and b is a regression exponent (Orndorff & Stamm, 1997). The total suspended sediment values measured for the reach along with their corresponding discharge values over the time period of interest were modeled using this relation and curve fitting tools found in Matlab. The relation between these two datasets was found to be as follows:

The suspended sediment data, corresponding water discharge values, and modeled relation between these datasets are shown in the figure below.

Following the determination of an appropriate total suspended sediment rating curve for the Rio Grande at Albuquerque, the daily flow data was used to generate a lognormal probability density function in order to determine discharge probabilities (Orndorff & Stamm, 1997). The probability density function for daily discharge from 1973 to 2013 for the Rio Grande at Albuquerque is shown below:

The frequency of each discharge is then computed by multiplying its probability by the total number of days under consideration. Finally, the sediment rating curve that was previously determined for this gauge was used to calculate the sediment discharge for each discharge value over the period of record. This sediment discharge value (tons per day) was multiplied by the discharge frequency (days) in order to determine a sediment load value (tons) for each discharge for the period of record (Orndorff & Stamm, 1997). This relation is shown in the figure below.

The peak value in this curve is known as the effective discharge which is corresponds to the discharge that transports the largest fraction of sediment. As is shown in the figure above, the effective discharge for suspended sediment in the Rio Grande at Albuquerque is approximately 1120 cfs.

In order to determine the discharge required for channel forming processes, it is important to separate the bed material sediment transport from the suspended sediment transport analyzed above. This information was found by removing the percent of sediment smaller than 0.062 mm (silt/clay range) from the suspended sediment data, a protocol outlined by Mussetter Engineering in their report on the geomorphology and sedimentology of the Middle Rio Grande. Again, a sediment rating curve was developed in order to show the relation between water discharge and bed material sediment discharge. This relation for bed load is modeled by the following equation and is shown in the figure below:





The same lognormal probability density function and flow frequency determined for daily discharge values from 1973 to 2013 was applied to the analysis of bed material transport. The sediment rating curve derived for bed material transport was applied to each daily discharge value in order to determine its corresponding sediment discharge. Finally, this sediment discharge value was multiplied by the discharge frequency in order to determine the sediment load value for each discharge value. This curve is shown in the figure below:

The effective discharge value for bed load based on the results of this analysis is approximately 2030 cfs, as is shown in the figure above.

The sediment transport analysis above helps to characterize the geomorphological changes occurring in the Albuquerque reach of the Rio Grande. In a river system that is in theoretical equilibrium, the effective discharge is analogous to the bankfull discharge, the river discharge just before the river overbanks. The effective discharge values calculated above are significantly lower than the bankfull discharge of the Rio Grande. In this context, effective discharge can still be defined as the discharge that moves the most sediment the most frequently. It is important to note that, because these effective discharge values do not correspond to the bankfull discharge for the river, we can conclude that this discrepancy is in fact an indicator of the disequilibrium of the system, rather than a metric describing the natural dynamic shift in equilibrium caused by a river reaching its true bankfull discharge.

The effective discharge values calculated above occur relatively frequently over the hydrologic history of the Rio Grande after the construction of Cochiti Dam, as is shown in the probability density function for daily discharge values, and are much smaller than even the 2-year flood discharge value of approximately 5000 cfs. The high frequency of these highly effective sediment moving discharge values indicates that the system is currently in a state of degradation as suspended and bed material sediments are moved frequently and consistently through the system. This means that the Rio Grande in the Albuquerque reach has shifted completely from its historic natural tendency of aggradation to a state of degradation and incision.

The historical impacts on the geomorphology of the Rio Grande through the Albuquerque reach and the current implications of those impacts, along with modern river uses, have significantly restricted the availability of suitable habitat for both the Rio Grande Silvery Minnow and the Southwestern Willow Flycatcher. The continued degradation of the river along with declining water supplies decreases the likelihood that the flows required for beneficial overbank flooding will occur frequently enough in the future to make an impact on the recovery of these two endangered species.


 * Rio Grande Silvery Minnow**

The Rio Grande Silvery Minnow (Hybognathus amarus) has been listed as an endangered species since 1994. It was once distributed in both Texas and New Mexico in the Pecos River, through the Rio Grande basin and into the Big Bend National Park (Bestgen and Platania, 1991). The silvery minnow was first classified as a separate species for the first time recently and was soon after protected under the Endangered Species Act (Bestgen and Plantania 1991). However, the anthropogenic changes on the river have drastically reduced those rankings, which eventually resulted in the silvery minnow being put on the endangered species list within the next 40 years after the collection of 1955. The effects of extinction are uncertain and would likely have severe impacts on the several trophic levels, therefore efforts are currently being directed toward the recovery of the species.

The Albuquerque Reach of the Rio Grande is defined by the Bureau of Reclamation as the area between the Angustora Diversion (seen in the picture below) and the Isleta Diversion in the Middle Rio Grande. This area was determined to have the following barriers for silvery minnow success: maximum channel depth has doubled caused by bed incision, average depth increase from 3 feet to 6 feet during the 1990’s, increase in sediment size, reduced flooding and a shift from shallow and braided to a deep and meandering river system. These silvery minnow habitat confounders are a result of various anthropogenic engineering and impacts which were done in an effort to reduce flooding, increase agricultural productivity, reduce infrastructure damage, and meet compact deliveries the downstream users. By performing the river modifications, New Mexicans were able to reduce their evaporative losses, seepage losses and increase the available water for various beneficial uses. Environmental flows are not considered a beneficial use under current New Mexico water law. //Spawning// The exact spawning needs of the silvery minnow are still questionable, however there has been a convergence of evidence showing the need for a spring flood pulse. The pulse not only cues spawning, but it also provides successful spawning habitat in the inundated floodplain. The Biological Opinion of 2003 states the critical habitat needs for the silvery minnow and many restoration projects have centered their focuses with that habitat in mind. The need for backwaters or pools, slow moving and shallow waters, with the appropriate water temperatures for the various cues needed for successful recovery of the species. The Albuquerque Reach, as defined by the Bureau of Reclamation, has been one of the large focal points of restoration along the Rio Grande. Several projects have been focused around bank terracing so that the area would inundate at several different discharges, thus giving the minnow habitat at various times of the year. Specifically, habitat conducive for spawning has been a focus for the projects conducted by the Army Corp of Engineers.

The Army Corp of Engineers began construction in January of 2001 on the Middle Rio Grande Bosque Restoration Project. This project is set to remove some of the constraints on the river which have caused silvery minnow habitat reductions. This includes jetty jack removal, invasive species removal, species/fuel reduction, riparian gallery forest reduction, and several other goals, in an effort to restore native species and their habitat. This project is a 916 acre project that includes over 26 miles of the river reach and various project locations have been selected along that stretch. This restoration project is a collaboration between the Army Corp of Engineers, Middle Rio Grande Conservancy District, City of Albuquerque Open Space and several other agencies. The budget for this project is 24.8 million dollars and has recently begun phase II.

//Predation// The natural predators of the silvery minnow are low in the natural state of the river. However, under the modified conditions and introduction of non-native species, the silvery minnow now has piscivorous predators such as largemouth and smallmouth bass, white bass and striped bass. This is especially a problem during spawning season when there is inadequate spawning habitat for the minnow and the eggs are carried down to Elephant Butte Reservoir and are consumed. Therefore, the habitat restoration projects in the Albuquerque Reach which are being developed, are increasing the probability of successful silvery minnow hatchings.

//Sustainability Recommendations// Recommendations for the Albuquerque Reach are expressed in the Biological Opinion and most of the current restoration projects seem to stay true to those recommendations. The primary concern is habitat for reproduction, a flood pulse large enough to cue spawning, and bank engineering to design areas conducive to the silvery minnow during various discharges. There has been an increased focus to reestablish floodplain connectivity also with this reach, given the current restrictions of infrastructure. More research is however needed on the silvery minnow’s selective food choices under conditions where various algae, diatoms and invertebrates are present. Another recommendation would be to maintain constant connectivity with the lower Isleta Reach. This is important for genetic diversity and gene flow since the silvery minnow may not migrate up or downstream. Maintaining a constant relationship becomes more important in that case to keep selective pressures constant on the species and allow for positive selection which, in turn, increases the resiliency of the species.

An increase in environmental flows and the minimum flows in the Albuquerque Reach would also benefit the sustainability of the species. The minimum flow gauging locations would also be recommended for change. The current gaging station for the minimum flows is at the Rio Grande at Albuquerque (USGS gage 08330000). This gage is located at the Central Street Bridge and reduces the range of which the minnow can inhabit during a significant proportion of the year. Downstream users divert heavily below this gage and cause the river to be intermittent. Although the Rio Grande was historically intermittent before the Cochiti Dam construction, due to the reduced habitat and increased river constraints, river drying is a concern. It would be more beneficial for the minnow if there were minimum flows at several gages starting at Central Street Bridge, as well as several others downstream sites. This would require policies that would change the way downstream users use water.


 * Southwestern Willow Flycatcher**

__Distribution__

The Southwestern Willow Flycatcher (Empidonax traillii extimus hereafter referred to as Flycatcher) is a small, gray to green bird with a white throat area, a green to olive breast, a yellow stomach area, and two observable wing bars (fws.gov). The Flycatcher is a relative of other Willow Flycatchers (sbsc.wr.usgs.gov) and is visually almost indistinguishable from many of these Willow Flycatcher species. Flycatchers are distinguished by their unique call, which is distinct from the other Willow Flycatcher species (fws.gov). Historically, Flycatchers nest between May and June and have a clutch size between 2 and 5 eggs, and young arrive in early and middle July. Second clutches in a single season are not attempted unless the first clutch is unsuccessful (fws.gov). Figure 11 shows the relation of Flycatchers (E.t.extimus) in relation to other Willow flycatchers. The Flycatcher was federally listed as an endangered species in February of 1995. At the time, best historical information at the time had placed nesting birds in a large swath of territory in all of the states listed in its range (fws.gov) Information at the time of the Flycatcher’s listing placed territories at nearly half of historical territory estimates and estimates of 500-1000 breeding pairs in existence (fws.gov).



Flycatchers also migrate during winter months. They spend between around September to May in areas south of the United States: Mexico, Central America, and possibly northern parts of South America (fws.gov). The Pacific lowlands of Costa Rica, in Central America appear to be very important territory for spending winter months for the Flycatcher (Paxton et al. 2011). They return to their nesting areas from around May through September. The range and distribution of Flycatchers is smaller than it was historically, which is a product of habitat loss (fws.gov). Changes to both the condition and sheer availability of habitat has caused Flycatcher populations to decline, which ultimately led to their listing as a federally endangered species in the United states. Changes to critical habitat in the United States are an important source of stressors for the Flycatcher. Additionally, changes or depletion of habitat in wintering habitat, such as the territory in Costa Rica, or areas between the United States and over-winter sites could be contributing to the decline of the Flycatcher.

The elevation variation, combined with several other environmental variables makes the distribution of Flycatchers seasonally immense. They breed anywhere from sea level to altitudes of over 2,600 meters above sea level (fws.gov). Around 1,300 documented territories suitable for the Flycatcher exist in these altitude ranges, however most of these territories tend to exist on the lower spectrum of the altitude range (fws.gov). These 1,300 territories were designated as areas that housed one or more flycatchers in a single breeding season (fws.gov). In the United States, under the endangered species act (ESA), some of these recognized territories can fall under the classification of “critical habitat”. Critical habitat, as set out in the endangered species act is essentially habitat that specifies a geographic area with certain characteristics and benefits provided to a species that help to ensure the conservation, with the goal of eventual recovery, of an endangered or threatened species (fws.gov). In January of 2013, the United States Fish and Wildlife Service revised its 2005 critical habitat designation for the Flycatcher, and in February, 2013 the changes took effect. Changes made to the critical habitat included additions to the 2005 critical habitat area. An area of 1,227 stream miles in the 100-year floodplain of wetted areas of California, Arizona, Nevada, Utah, Colorado, and New Mexico, totaling almost 209,000 acres was added to the critical habitat of the Flycatcher. This helps to prevent against modification to the land without specific permissions, under penalty of federal law.

__Habitat__

Flycatcher habitat is a mixture of types of riparian vegetation on or along rivers, streams, reservoirs, and other types of wetted areas (fws.gov). According to the Designation of Critical Habitat for Southwestern Willow Flycatcher, Flycatcher nesting habitat is very closely associated with year-round stream flow that is capable of sustaining the vegetation that is needed for supplying both nesting habitat and also sheltering habitats as well (fws.gov). Flycatcher’s habitat consists of crowded territories of combined tree and dense shrubby undergrowth, coupled with proximity to a water source that will, at times provide wetted soil due to groundwater levels, or overbank flooding (fws.gov). There are several tree species that constitute Flycatcher habitat: Gooding’s willow (Salix gooddingii), Coyote willow (Salix exigua), Geyers willow (Salix geyerana),Arroyo willow (Salix lasiolepis), Red willow (Salix laevigata), Yewleaf willow (Salix taxifolia), Boxelder (Acer negundo), Tamarisk (saltcedar) (Tamarix ramosissima), and Russian olive (Eleagnus angustifolia) (fws.gov). It is rare for Flycatchers to nest in an area where there are no willows, Tamarisk, or both present (fws.gov). Flycatchers prefer areas dominated by natural vegetation. However, about 28% of breeding territories are in areas dominated by the exotic species tamarisk (Durst et al. 2008). Some of areas that have the highest number amount of breeding territory are the middle Rio Grande and the upper Gila River (fws.gov).

Riparian areas of the southwestern United States are an extremely important area for biodiversity. Over 50% of southwestern bird species are in some way fundamentally and inexorably linked to riparian habitat. This becomes especially important since riparian habitat only encompasses 1% of the landscape of the southwestern United States (Hatten et al. 2010). This has important consequences at an ecosystem level, and places importance on the conservation of both the species that occupy these riparian areas. Important pockets of biodiversity rely on riparian areas, and some species that pass through the southwest use riparian areas as transportation areas, or stopping points with a destination outside of the southwest. Affects to non-native species to the southwest may be incurred with a degradation of the riparian areas, in addition to harm to native species.

One of the main causes for the decline of the Flycatcher is the degradation of its habitat. This degradation is due to a combination of: Decline in the hydrology that allows for the riparian habitat that houses the Flycatcher to be created, introduction and proliferation of exotic species, and anthropogenic habitat destruction (fws.gov). Climate change is also likely to have an impact on Flycatcher habitat, but the magnitude and extent of that impact is not yet known. One of the main constituents that alters a hydrograph and causes harm to the Flycatcher is dams (Hatten et al. 2010). A dam interrupts the natural hydrograph of an area which can in turn cause a disruption to natural flood and overbanking regimes. In addition, rivers tend to lose their natural sinuosity and become more channelized (Hatten et al. 2010). The southwestern United States has a characteristically different hydrograph from other areas of the United States. Areas that are flooded and inundated for several years can experience times when they are then tens of meters away from flow for several years as well (fws.gov). Riparian areas along the middle Rio Grande are adapted to these annual to decadal fluctuations. These fluctuations, combined with natural sinuosity, allowed for the creation of a vast, wide floodplain in the past, which could have provided significant habitat for the Flycatcher.

__Food__

One of the most important aspects that influences life history of a species can be diet (Durst et al. 2008). It influences habitat use, physiology, survival rates, reproductive success, and geographical patterns (Durst et al. 2008). Factors of how birds gather food can arise and have intra-species variation. Some of these factors are age, sex, and habitat structure (Durst et al. 2008).

Flycatchers are insectivores, and are basically generalists, meaning they do not prefer one insect type above another. They eat many flying species of insects including bees, wasps, butterflies, moths, caterpillars, ants, dragonflies, flies (fws.gov). Flycatchers have also been known to select for hatchlings of aquatic insects (fws.gov). Also there have been instances where they will eat small pieces of fruit, as well (fws.gov). Flycatchers use a “sit and wait” technique to acquire food resources. Reduction of suitable habitat for insects in a given range may have additional impacts on Flycatcher's ability to successfully nest in the affected area.

Flycatcher food resource availability is largely a product of what conditions and habitats are beneficial to its prey items. This habitat is generally influenced by vegetation density, how close water is, the hydrology of the area, and soil water levels, and saturation statistics (fws.gov). Hand in hand with the issues that altered hydrology presents to habitat structure, are issues with food availability. Altered hydrology affects the natural trophic structure of an environment from the ground up, fewer primary producers could mean less energy conversion, which in turn can lead to a decline in available biomass for consumption.

__Albuquerque Reach__

The Albuquerque reach of the Rio Grande is a difficult place for the Flycatcher to inhabit. Virtually every mile of the river has been impacted by humans in some way. Figure 12 represents a map of the revised 2013 critical habitat based on the entire range of the Flycatcher. One of the most difficult dilemmas facing Flycatchers in the Albuquerque reach is habitat availability. Because riparian habitat can be incredibly dynamic, small patches can be subject to many natural and anthropogenic factors that can either facilitate new growth, or hinder sustainability (Hatten and Sogge 2007). Additionally, there is data from the Bureau of Reclamation that suggests in some parts of the state, Flycatchers prefer a vegetation density of 2,800 trees per hectare and a thick vegetation canopy between 3m and 6m above the ground (USBR). These two combinations of factors make new and existing Flycatcher habitat in the Albuquerque reach difficult to develop and maintain. Flycatchers also prefer stands with immediate proximity to water (fws.gov), which further limits habitat availability in the Albuquerque reach. In the 2013 critical habitat revision made by the fish and wildlife service, the Albuquerque reach of the Rio Grande was not listed as critical habitat for the Flycatcher. This is likely due to the lack of suitable factors and areas that would be able to sustain breeding Flycatchers for a meaningful amount of time



In 2007 a study by Hatten and Sogge used GIS to analyze potential habitat in a corridor of area along the Rio Grande in central New Mexico. Their study took into account water availability, photosynthetic activity, floodplain area, and vegetation density. They split their categories for suitable Flycatcher habitat into 5 different categories, with a 20% increased likelihood per category for an area to house habitat suitable for nesting Flycatchers, with 1 being the most unsuitable for Flycatcher nesting potential. Figure 13 is a GIS generated map from their study in the Albuquerque reach. Most areas in the Albuquerque reach are largely unsuitable according to this map analysis. However there are pockets of habitat that could viably support the flycatcher.



In 2012 the Albuquerque Water Utility Authority proposed a project on a site in the Albuquerque reach for restoration of native vegetation, as well as a buffer zone. Figures 14 and 15 are of the proposed sites. The proposed restoration was to excavate the floodplain to groundwater depth to ensure consistent soil moisture content and to plant Goodings willows and Coyote willows in an approximately 10 acre area. Additionally, a 10 acre area farther away from the river but connected to the restoration area was also planned to be seeded with native vegetation, including Cottonwoods (usbr.gov).





The proposed sites would require groundwater levels that were close to the surface for a consistent amount of time in order not only establish, but to sustain vegetation planted at the site. If successful, and if regular inundation and overbanking occurs at the site, further habitat could be created from spread of seeds of native willow plants. There is no argument that the proposed habitat restoration has great potential to restore native Flycatcher breeding habitat. However, regular inundation would be required to ensure that the habitat is successful. Actualizing this has become difficult in a reach with an incredibly altered hydrograph and increasingly limited water supply. 10 acres is also a small portion of habitat, however it does ensure proximity to water at almost all of its locations. The proposal used well established restoration techniques, however an establishment of certain parameters to measure success would need to be developed and monitoring those parameters would need to take place to determine if the plan was a success. Also proposed in the plan are both an alternative action, and no action plan.


 * Restoration Recommendations**

The Rio Grande Silvery Minnow recovery is severely limited by anthropogenic confounders. In order to effectively recover the species, the water usage in their endemic reach must be changed. Their habitat has been severely altered by the dams put in place by limiting their ability to move upstream and the natural hydrograph has been altered significantly. The resident need to control the water to meet compact deliveries, prevent flooding, and control water for agriculture has reduced the flood peak, reduced floodplain connectivity, reduced overbank flooding, and changed the habitat features which the silvery minnow historically relied on for propagation, spawning, etc. Therefore, in order to recover the species, there needs to be more reach connectivity, a snowmelt pulse moving through the system at an appropriate time, overbank flooding for a long enough duration and with a slow descending recession, and areas of the river which provide adequate suitability for successful egg hatching. This would require reduced periods of drying of the river downstream of the Albuquerque reach, decreased watch withholdings upstream at Cochiti Dam, decreased infrastructure in the floodplain, and a change is water allocation during periods of drought.

Under the various restoration projects, there are a series of habitat and channel engineering that have, and are due to commence. Banks have been engineered to inundate at depths as low as 500 cfs up to 2000 cfs in the Middle Rio Grande Bosque Restoration Project. Other restoration techniques which are being implemented are engineering habitat conditions in vegetated island modification, embayment engineering, backwater areas, riverbank expansion, drain enhancement, jetty jack removal and possibly the use of large woody debris. The second phase of the Middle Rio Grande Bosque Restoration Project is due to modify 16 islands using various techniques, terrace/expand the riverbank at 11 locations, put in ephemeral channels at 2 sites, enhance drainage and put in backwater channels at 1 site and put in embayment channels and removal of jetty jacks at 2 sites. The picture below shows the various restoration site locations which have been implemented along the Rio Grande. The high concentration in the Albuquerque Reach is visible as well as a high concentration in the San Marcial Reach. This photo was created by the Fish and Wildlife Service.

Restoration of Flycatcher habitat in the Albuquerque reach would require a long-term, and financially intensive operation. In order to facilitate conservation and eventually recovery, the primary focus would be the restoration of native vegetation, and restoration of the a more historic hydrograph, focusing on increased overbanking and peak flows. Native vegetation would provide both the dense mid-canopy and shrub habitat that Flycatchers prefer. A wider floodplain would allow for the recruitment opportunities and growth of vegetation resulting in an increase in available habitat for nesting Flycatchers. Bank lowering would provide some of the necessary habitat for this type of recruitment, but is difficult and expensive in the Albuquerque reach. Increases in food availability in the form of increased insect abundance resulting from increased soil moisture would also be favorable for Flycatcher restoration. If restoration efforts were made solely for the purpose of increasing Flycatcher populations, focus would be mainly on two areas. Restoring areas of critical habitat, native willow species, specifically, and restoring a more natural hydrograph, including increased environmental and base flows to the Albuquerque reach. Decreasing channelization, increasing natural sinuosity and natural braids to the channel could also increase natural habitat as well. This can be done mechanically, however not without great damage to current infrastructure. A highly urbanized area combined with controlled dam releases and channelization with the intent of bank preservation combine with altered flood regimes to cause detriment to critical habitat and food availability. Simply put, the most important factor is the hydrology of the area, and in the current physical and managerial structure of the Albuquerque reach, large-scale restoration seems unlikely. Allowing the Rio Grande to revert to historic conditions, including the removal of anthropogenic infrastructure, would be one of the best things that could be done for the Flycatcher in almost every sense.

The restoration of the natural geomorphological forms of the Rio Grande may help to provide new habitats based on the needs of the Rio Grande Silvery Minnow and the Southwestern Willow Flycatcher. Restoration projects aimed at creating these habitats through physical geomorphological changes could include bank lowering, the creation of ephemeral side channels, the construction of bank-line embayments, channel widening, the construction of gradient control structures, and the destabilization of islands and bars. Examples of these types of form-based restoration actions have already been implemented at several sites along the Rio Grande. Although restoration actions that have occurred in the Albuquerque reach of the Rio Grande have largely been form-based, it is our understanding that the success of many of these types of projects is precluded by the hydrologic constraints present in the system. Thus, the focus of our restoration recommendations for the Albuquerque reach of the Rio Grande will largely be based on hydrologic recommendations in order to reestablish the natural flow regime required for the life cycles of the two endangered species under consideration.

The anthropogenic impacts on the physical processes associated with the hydrology and geomorphology of the Albuquerque Reach can be seen on any trip to the river near Albuquerque. Levees and jetty jacks are prevalent features and performed the task of channeling the Rio Grande into a more controlled, narrow channel. With Cochiti Dam upstream controlling maximum discharges, the system’s hydrology has changed and in correlation, the geomorphology as well. As the hydrologic regime shifts further from the natural flow regime, floodplain connectivity has and continues to decrease. A qualitative assessment of floodplain inundation calculated with the use of a 1-dimensional model, HEC-RAS, shows that large portions of the channel banks are not overtopped at 5,000 cfs (Fig. X). Bankfull discharge has been observed to be an event associated with approximately a 1.5-year return period (Leopold et al., 1964). Using data collected at the Central Avenue USGS gauge since the construction of Cochiti Dam, a 1.5-year return period flow is approximately 3200 cfs. Even an event with a 50% chance of occurring in any given year is only about 4700 cfs. Therefore, one would expect that a discharge of 5000 cfs would be inundating the floodplain in most places if the system were in dynamic equilibrium. The lack of inundation suggests that the channel is incised and the floodplain is disconnected from the main channel, preventing recruitment of new SWFL habitat and reducing the channel complexity in which the RGSM thrives.



In order to combat the floodplain disconnection in such an urbanized reach, a combination of physical restoration projects and environmental flows will be necessary. Because of infrastructure and safety concerns, protection of the historical floodplains in the valley will remain strong and the riparian corridor will need to remain narrow. Therefore, the small-scale restoration projects will need to continue within the Albuquerque Reach, with a focus on low cost, easily maintained features. Equally, if not more important for these species, is ensuring flows are not only high enough to inundate these restoration features with consistent frequency, but also large enough to promote scouring of vegetated islands, scouring of floodplain-attached bars, and inundation of the floodplain promoting channel complexity. The overbanking analysis above suggests that flows of at least 5,000 cfs are necessary to inundate significant portions of the floodplain. However, with increasing temperatures, water supplies are likely to decrease, meaning in all likelihood lower amounts of water will be available for environmental flows. Because of this, the recommendation of this report is to annually inundate the restoration projects occurring within the Albuquerque Reach and create channel complexity at lower and more likely future flows. When wet years provide more water, it should be a reasonable expectation to produce a sustained environmental pulse of greater magnitude. The goal of such a pulse would be to create geomorphic change of islands, bars, and the floodplain. Finally, realistic solutions for decreasing water consumption must be a goal for the near future. If the RGSM and SWFL are to be saved, they will require a portion of available water and a more natural flow regime. Both species have lived for a long time in extremely variable conditions; however, the conditions of our altered system must be changed back to within the limits of their adaptability.


 * Conclusion**

The impacts to the Rio Grande in the Albuquerque reach caused by a long history of man-made degradation and manipulation will be difficult to overcome with any type of restoration action. Regardless of this difficulty, the sustainability needs of the Rio Grande Silvery Minnow and the Southwestern Willow Flycatcher must be addressed. The best way to tackle this problem may be the continued maintenance of restoration projects that have already been implemented along the reach. This maintenance may be achieved through the use of environmental flow regimes, which be the strongest way to ensure the eventual success of these two endangered species.


 * Resources**

//Hydrology//

Berli, M., L. Chen, and M. Young, 2008. Wildfire Effects on Watershed Hydrologic Processes: An Introduction for Hydraulic Engineers, Watershed Managers, and Planners. Prepared by the Desert Research Institute. U.S. Army Corps of Engineers Publication No. 41243.

Buhl, K.J., 2010. Evaluation of estrogenic biomarkers in Rio Grande Silvery Minnow and the assessment of subchronic toxicity and estrogenicity of selectected wastewater treatment effluents of the silvery minnow. Interagency Acquisition No. 08-AA-40-2823.

Bureau of Reclamation (BOR), 2012. Joint Biological Assessment: Bureau of Reclamation and Non-Federal Water Management and Maintenance Activities on the Middle Rio Grande, New Mexico.

Llewellyn, D. and S. Vaddey, 2013. West-Wide Climate Risk Assessment: Upper Rio Grande Impact Assessment. U.S. Department of the Interior Bureau of Reclamation.

Middle Rio Grande – Albuquerque Reach Watershed Group, 2008. Middle Rio Grande – Albuquerque Reach Watershed Restoration Action Strategy. Supported by the Clean Water Act Grant.

Phillips, F.M., G.E. Hall, and M.E. Black, 2011. Reining in the Rio Grande: People, Land, and Water. University of New Mexico Press, Albuquerque, New Mexico, pp. 252.

Poff, N.L., J.D. Allan, M.B. Bain, J.R. Karr, K.L. Prestegaard, B.D. Richter, R.E. Sparks, and J.C. Stromberg, 1997. The Natural Flow Regime. //Bioscience// 47(11): 769-784.

Population Estimates and Projections Program (PEPP), 2008. A Report on Historical and Future Population Dynamics in New Mexico Water Planning Regions. Bureau of Business and Economic Research, University of New Mexico.

Western Regional Climate Center (WRCC). www.wrcc.dri.edu. WBAN: 23050 & 298011.

//Geomorphology//

Biedenharn, D. S. and R. R. Copeland, 2000. Effective discharge calculation. Technical Note, U.S. Army Corps of Engineers. Vicksburg, MS.

Crawford et al., 1993. Middle Rio Grande ecosystem: Bosque biological management plan. Middle Rio Grande Biological Interagency Team. Albuquerque, NM.

Graf, W.L., 1994. Plutonium and the Rio Grande: Environmental change and contamination in the nuclear age. Oxford University Press, New York.

Mussetter Engineering, Inc. (MEI), 2002. Geomorphic and Sedimentologic Investigations of the Middle Rio Grande between Cochiti Dam and Elephant Butte Reservoir. Report submitted to the New Mexico Interstate Stream Commission, Albuquerque, NM.

Orndorff, R. L. and J. F. Stamm, 1997. A laboratory exercise introducing the concept of effective discharge in fluvial geomorphology. Journal of Geoscience Education, v. 45. 326-330.

Scurlock, D., 1998. From the Rio to the Sierra: an environmental history of the Middle Rio Grande Basin. RMRS-GTR-5. Rocky Mountain Research Station, Forest Service, U.S. Department of Agriculture, Fort Collins, CO.

Thompson, J.C., 1965. Symposium on Channel Stabilization Problems: Chapter I- Channel Stabilization, Middle Rio Grade Project. U.S. Army Corps of Engineers. Vicksburg, MS.

//Rio Grande Silvery Minnow//

Bestgen, K., Plantania, S. 1991. Status and conservation of the Rio Grande silvery minnow Hybognathus amarus. The Southwester Naturalist. Vol 26 (2): 225-232.

Medley, C., Shirey, P. 2013. Review and Reinterpretation of Rio Grande silvery minnow reproductive ecology using egg biology, life history, hydrology and geomorphology information. Ecohydrology.

Middle Rio Grande Endangered Species Act Collaborative Program. 2010. Rio Grande Silvery Minnow Augmentation in the Middle Rio Grande, New Mexico. Annual Report 2008.

Molles, M., Crawford, C., Ellis, L., Valett, H., Dahm, C.1998. Managed flooding reorganizes riparian forest ecosystems along the middle Rio Grande in New Mexico. BioScience. Vol 48 (9): 749-756.

//Southwestern Willow Flycatcher//

Durst, S. L., T. C. Theimer, E. H. Paxton, and M. K. Sogge. 2008. Age, Habitat, and Yearly Variation in the Diet of a Generalist Insectivore, The Southwestern Willow Flycatcher. Condor 110:514-525.

Hatten, J. R., E. H. Paxton, and M. K. Sogge. 2010. Modeling the dynamic habitat and breeding population of Southwestern Willow Flycatcher. Ecological Modelling 221:1674-1686.

Paxton, E. H., P. Unitt, M. K. Sogge, M. Whitfield, and P. Keim. 2011. Winter Distribution of Willowflycatcher Subspecies. Condor 113:608-618.

Southwestern Willow Flycatcher (Empidonax traillii extimus), Available at: []

Some Commonly Asked Questions About the Southwestern Willow Flycatcher, Available at []

Endangered and Threatened Wildlife and Plants; Designation of Revised Critical Habitat for Southwestern Willow Flycatcher, Available at: []

Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for Southwestern Willow Flycatcher; Final Rule, Available at: []

Southwestern Willow Flycatcher Critical Habitat Revision Questions and Answers, Available at: []

Using a Remote Sensing/GIS Model to Predict Southwestern Willow Flycatcher Breeding Habitat along the Rio Grande, New Mexico, Available at: @http://pubs.usgs.gov/of/2007/1207/of2007-1207.pdf

Vegetation quantification of Southwestern Willow Flycatcher nest sites. Available at: @http://www.usbr.gov/pmts/fish/Reports/SWFL%20nest%20veg%20quant%2004-06.pdf

Albuquerque Bernalillo County Water Utility Authority Southwestern Willow Flycatcher Habitat Restoration Project Environmental Assessment. Available at: [|http://www.usbr.gov/uc/albuq/envdocs/ea/bernalillo/SWflycatcher/EA.pd]

Brief Outline Paper Framework
 * Previous requirements and revisions:**


 * Team Contact Information:**

Aubrey Eckert-Gallup- aubreyeckert@gmail.com Eddie O'Brien - eobrien@unm.edu Colin Byrne - cfbyrne@unm.edu Ryan Kelly - rkelly@unm.edu

 · Southwestern Willow Flycatcher  · -Historical Data o -Life history and general facts (such as nesting habits/food preference). o -Historical Habitat/current habitat  · -Hydrological needs (Ideal) in Albuquerque reach <span style="display: block; height: 1px; left: -40px; margin: 0in 0in 0in 1in; overflow: hidden; position: absolute; text-indent: -0.25in; top: 305.5px; width: 1px;">o -necessities for habitat creation/Seed dispersal requirements <span style="display: block; height: 1px; left: -40px; margin: 0in 0in 0in 1.5in; overflow: hidden; position: absolute; text-indent: -0.25in; top: 305.5px; width: 1px;"> § -Hydrograph <span style="display: block; height: 1px; left: -40px; margin: 0in 0in 0in 1.5in; overflow: hidden; position: absolute; text-indent: -0.25in; top: 305.5px; width: 1px;"> § -Bank connectivity <span style="display: block; height: 1px; left: -40px; margin: 0in 0in 0in 1.5in; overflow: hidden; position: absolute; text-indent: -0.25in; top: 305.5px; width: 1px;"> § -Rates of change <span style="display: block; height: 1px; left: -40px; margin: 0in 0in 0in 1.5in; overflow: hidden; position: absolute; text-indent: -0.25in; top: 305.5px; width: 1px;"> § -Reach connectivity <span style="display: block; height: 1px; left: -40px; margin: 0in 0in 0in 1in; overflow: hidden; position: absolute; text-indent: -0.25in; top: 305.5px; width: 1px;">o -Necessities for food source maintenance <span style="display: block; height: 1px; left: -40px; margin: 0in 0in 0in 1.5in; overflow: hidden; position: absolute; text-indent: -0.25in; top: 305.5px; width: 1px;"> § -Hydrograph <span style="display: block; height: 1px; left: -40px; margin: 0in 0in 0in 1.5in; overflow: hidden; position: absolute; text-indent: -0.25in; top: 305.5px; width: 1px;"> § -Bank connectivity <span style="display: block; height: 1px; left: -40px; margin: 0in 0in 0in 1.5in; overflow: hidden; position: absolute; text-indent: -0.25in; top: 305.5px; width: 1px;"> § -Rates of change <span style="display: block; height: 1px; left: -40px; margin: 0in 0in 0in 1.5in; overflow: hidden; position: absolute; text-indent: -0.25in; top: 305.5px; width: 1px;"> § -Reach connectivity <span style="display: block; height: 1px; left: -40px; margin: 0in 0in 0in 1in; overflow: hidden; position: absolute; text-indent: -0.25in; top: 305.5px; width: 1px;">o -Year round base flow/conditions when SWFC not present <span style="display: block; height: 1px; left: -40px; margin-bottom: 0in; overflow: hidden; position: absolute; text-indent: -0.25in; top: 305.5px; width: 1px;"> · -Realistic conditions (Maybe have a section for this?) Could be in conclusions or later.