Monitoring the Nisqually Delta
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This is the presentation given by Kelley Turner at the August 2011 Nisqually River Council meeting.
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Monitoring the Nisqually Delta
- 1. Monitoring the Nisqually Delta Kelley TurnerUSGS Western Ecological Research CenterJohn Takekawa (Project Principal Investigator) & Isa Woo (Project Coordinator) Nisqually River Council Meeting 19 August 2011 Olympia, WA
- 2. Estuarine Habitat Loss Puget Sound 2,500 km2 > 80% historic estuarine habitat lost Active pursuit of the recovery of Puget Sound ecosystems through estuarine restoration Nisqually Delta Restorations
- 3. Nisqually Delta Restorations Nisqually River McAllister Creek Pilot 9 acres restored in 1996 Phase I 31 acres restored in 2002 Phase II 100 acres restored in 2006 Nisqually NWR 762 acres restored in 2009 2009, 762 acres 1996, 9 acres 2002, 31 acres 2006, 100 acres
- 5. Mudflats
- 9. Riparian forested wetlandsJ. Takekawa,Jan 2011
- 10. Estuarine habitats are places of change
- 12. on restoration effectiveness
- 13. as a measure of accountability
- 14. for land managers to make management decisions
- 17. July 2009 Source: USGS
- 18. December 2009 Source: USGS
- 19. July 2010 Source: USGS
- 20. July 2011 Source: USGS
- 21. Shannon North Post Dike Removal August 2011
- 22. Hydrology
- 23. Hydrology
- 25. Historic Channels of the Nisqually River Delta - 1878 Historic water channels in the Nisqually Delta. Estuary restoration will reconnect 21.4 miles of sloughs. Based on 1878 T-Sheets by Collins & Montgomery of UW. J. Cutler of Nisqually Tribe, 2007.
- 26. Nisqually Delta Channel Development 1878 December 2009 2005 Sources: US Coast Survey - Topography of Puget Sound - Nisqually to Totten Inlet, US Geological Survey, Washington State Department of Natural Resources/University of Washington Puget Sound River History Project. Data derived by Jennifer Cutler Cartography by Jennifer Cutler, Nisqually Indian Tribe Cartography by Heather Minnella, USGS WERC
- 29. lowest average elevation (i.e. deepest)
- 30. more developed and scoured
- 31. Shannon slough
- 32. highest average elevation (i.e. shallowest)
- 35. Marsh Elevation Mapping Pilot, 1996 Phase I, 2002
- 37. Species Richness by Elevation
- 38. -1.122 m 2.996 m 2.713 m Weinmann, F., et al. Wetland Plants of the Pacific Northwest. Seattle: U.S. Army Corps of Engineers, 1984. Tidal datum elevations from NOAA Dupont Wharf, Nisqually Reach tide station (cite?)
- 40. Plant Elevation Ranges © La Maison Léon-Provancher, 2009
- 41. Plant Elevation Ranges © Sandy Richard, 2008
- 42. Plant Elevation Ranges © Peter Baye, 2007
- 43. Plant Elevation Ranges © Peter Baye, 2007
- 46. Invasive Species
- 47. Continuous currents and sediment flux Trapping inLake Alder? Quarterlycross-sectionprofiles StudyingLake Alder FloodTransport? Ebb Transport Nearshore Response and Forecasting Nearshore Response and Forecasting Develop sediment budget: sufficient for marsh to keep pace with sea-level rise? 750 ac Goal1: Quantify net sediment flux in or out Goal2: Determine processes that transport sediment to/from delta
- 48. Surface Elevation Tables (SET) Photo: Jesse Barham
- 49. Surface Elevation Tables NNWR Phase II Reference
- 51. Monitor nearshore invertebrate community (food-prey resource) response to new salt marsh, climate change Nearshore Response and Forecasting Annelida - Manayunkia aestuarina WWU Arthropoda – Muscidae larvae Valley City State University
- 52. Monitor nearshore invertebrate community (food-prey resource) response to new salt marsh, climate change Nearshore Response and Forecasting
- 53. Bird Monitoring
- 54. Bird Abundance by Foraging Guild Dike removal
- 57. Project Partners and Collaborators Funded by EPA, ESRP, FWS and Students in Support of Native American Relations USGS Western Ecological Research Center J. Y. Takekawa (Project Principal Investigator), I. Woo (Project Coordinator), J. Shinn, A. Naljahih, H. Vaska, S. Bishop, J. Felis, B. Perry, L. Smith, W. Chan, E. Flynn, TESC Graduate Students (L. Belleveau & H. Allgood), UW Tacoma Intern (H. Minnella), Nicholls State University Intern (J. Bell) Nisqually National Wildlife Refuge J. Takekawa, D. Roster, J. Barham,M. Bailey and Refuge Volunteers Nisqually Indian Tribe J. Dorner, F. Leischner, E. Perez J. Cutler and S. Hodgson Nisqually River Foundation M. Holt, C. Iverson, A. David Ducks Unlimited D. Golner, S. Liske and P. Schulte Avian Design C. Fox USGS Patuxent Wildlife Research Center G. Guntenspergen, J. Lynch and J. Olker USGS Pacific Coastal and Marine Geology E. Grossman, P. Swarzenski, R. Kayen and D. Finlayson USGS Western Fisheries Research Center S. Rubin, K. Larsen and A. Lind-Null USGS Washington Water Science Center R. Dinicola, C. Curran Washington Department of Fish and Wildlife M. Hayes Nisqually Reach Nature Center D. Hull
Notes de l'éditeur
- Thank you for inviting me to speak today. I will be presenting preliminary restoration results for our collaborative work with multiple USGS scientists, the Nisqually Tribe, and Nisqually NWR. I gave this talk a couple of nights ago at the Refuge Summer Lecture series, so please excuse me if some of the material I’m covering is a bit of a review for you.
- NISQUALLY DELTA RESTORATIONS - Combined with earlier restorations conducted by the Nisqually Tribe, the Nisqually Refuge restoration is restoring 900 acres of estuarine habitat, the largest tidal wetland restoration in Puget Sound.
- ESTUARIES – So lets talk a little about what an estuary is and why they are so important. As you know, and estuary is place where freshwater and saltwater mix. Estuarine habitats in the Nisqually include open water, mudflats, tidal channels, tidal marshes and freshwater and riparian forested wetlands.
- ESTUARINE HABITATS ARE PLACES OF CHANGE – INSERT TIMELAPSE VIDEO HEREEstuarine habitats are also unique in that they are places of change. To illustrate this, I would like to show a time lapse video taken from the boardwalk, looking north towards the Puget Sound. Changes in water level with incoming and outgoing tides also leads to changes in temperature. When the tide is out, there can be sunbaked mud and when the tide is in, cooler temperatures. Tides and rivers also bring changes in salinity, sometimes an area can be mostly freshwater and other times mostly saltwater.
- WHY MONITOR? – So why is it important to monitor biological and physical changes to the Nisqually estuary as a result of restoration actions? Monitoring has been described as the financial equivalent of accounting, and is critical for project evaluation (Lee 1993). Monitoring provides information on restoration progress and program effectiveness, provides a measure of accountability, and informs land managers with up to date information on whether or not restoration actions are having the intended outcome and allows for interventions when unexpected changes occur. Restoration monitoring also adds to the collective scientific knowledge and understanding for the restoration community as a whole. For example, we are working with several restoration programs throughout the Pacific Northwest and West coast to share information and further everyone’s understanding the cumulative effects of estuary restoration.
- NISQUALLY DELTA APPLIED STUDIES AND MONITORING - This is a map detailing our monitoring plan for the Nisqually Estuary. The various symbols represent locations where different biophysical monitoring work is taking place. To integrate and maximize research efforts, we have coordinated several studies which fall under broad research objectives. Our experimental design is adjusted for each research objective. Our first objective is change detection through monitoring. This objective, is really like a thread weaving through all of our objectives. It includes all biophysical monitoring in all study sites within the estuary and will help us to determine the success of the restoration project along with long term changes to the estuary. Our second objective is to compare tidal marsh restoration projects by age. To do this we are not only including the recently opened Nisqually Refuge Restoration Site, but also sampling at the Nisqually Tribe’s three restoration sites introduced to tidal flow, 5, 9, and 15 years ago. We have also included a reference marsh that has never been diked to serve as an example of a functioning marsh in the estuary. The third objective looks at the offshore to onshore gradient of biotic and abiotic factors as you move from tidal flats to tidal marsh. To answer this question, we are sampling along four north to south transects. At a finer level, within the restoration area we have established monitoring stations at the mouth, middle, and upper reaches of five historic channels. Our fourth objective is to look at food web dynamics. We are currently working with the Nisqually Indian Tribe and USGS Western Fisheries Research Center to conduct a fish diet study at four study sites that I will provide more detail on later.Our fifth objective is a methods comparison of Rapid versus Intensive monitoring which is being built upon a national salt marsh integrity study (Glenn Guntenspergen and Hilary Neckles). For this study we have identified three sites, a historic channel within the Nisqually Refuge Restoration Site, the Nisqually Tribe Phase II Restoration Project, and the Reference Marsh, where we are conducting both rapid and intensive vegetation monitoring. The final objective is a tidal marsh colonization experiment, which is testing the effectiveness of four different land use treatments such as mowing and disking, in both building sediment and facilitating salt marsh vegetation colonization.
- MONITORING STATIONS – A key component of our monitoring strategy is to have monitoring stations throughout the Delta as shown in the previous map. These monitoring stations allow us to have coordinated sampling of a suite of physical and biological parameters for greater spatial relationships. For example, by measuring multiple biological and physical metrics in the same location, I can look at how elevation changes influence vegetation colonization, or how water quality effects benthic invertebrate populations. So what does a monitoring station look like? You may have noticed as you walked out on the boardwalk towards the McAllister Creek overlook, a series of PVC pipes in the ground next to Shannon Slough. These are sediment measurement pins at our Shannon Slough North monitoring station. At this station we also have a water level and quality logger, a surface elevation table for measuring changes in elevation, a vegetation transects and a channel cross section. We also measure bird populations monthly at the station and collect benthic invertebrates annually.
- ESTUARINE HABITAT INFLUENCE DIAGRAM – Now before I present monitoring results, lets take a little time to talk about little bit more about how all of these biological and physical parameters we measure influence eachother. This conceptual model describes the interactions among system drivers in estuarine habitat development and extent. First, there are overarching climate drivers that can influence all of these ecosystem processes. And then we’ve broken up the different ecosystem processes into major groups: water, sediment, elevation and vegetation. Many of the processes within these groups are influenced by multiple factors indicated by the white arrows. For an example, lets follow one path of influence. If we start up at the sea level rise climate driver on the top right we see how it influences both tidal exchange and freshwater inflow in the water processes group. Lets stick with tidal exchange which in turn influences erosion, subsidence, decomposition and sedimentation and at the elevation level also influences inundation regimes and flooding. If we follow this path we see that inundation regimes influence vegetation dynamics and tidal marsh development and extent. If we were to move beyond tidal marsh development we would then see how this influences our biological communities. This model really emphasizes our approach to monitoring which is focused on the ecosystem level and linkages.I will come back to this diagram as we move through each ecosystem process. First I would like to look at the use of aerial photography to look at water, sediment, vegetation and estuarine habitat development and extent.
- JULY 2009 – This aerial was taken in July 2009 just before the dike removal on the Refuge.
- DECEMBER 2009 – In this December photo you can see water coming into the open channels in the Refuge restoration area.
- JULY 2010 – and vegetation coming in in July 2010.
- JULY 2011 – this phot was taken just last month and you can see that the hard boundary of the old dike is starting to fade away
- PHOTOPOINTS– we can also use photographs to look at restoration changes at a more localized level. This 360 degree panoramic photo is taken from the boardwalk (now that it is built) and looks out toward the Shannon North monitoring station. You can see the transition as the freshwater vegetation present in 2009 starts to die back and now in the photo taken just last week we can see tidal marsh plants coming in.
- HYDROLOGY – The rise and fall of tides along with freshwater inputs are the medium of energy exchange throughout an estuary carrying nutrients and sediment; creating elevational and salinity gradients; and providing access to the marsh for fish and other aquatic organisms. This map shows the locations of our fifteen water level loggers located throughout the Delta. Water level loggers are useful tools for helping us to understand tidal hydrodynamics within the restoration site and can be compared to predicted tides and the Nisqually River and adjacent sloughs outside the restoration area. Patterns within a hydrograph can also illustrate potentially insufficient drainage within the newly restored channels. Water level data is also a key component to tracking sea level rise.
- HYDROLOGY – This is a hydrograph from the upper reach of Shannon Slough, one the restored tidal channels in the Nisqually NWR. You can see it highlighted in yellow on the map. This is five days of data during a Spring tide in March of last year. The blue line shows tides within the restored channel and the pink line shows verified tides from the Tacoma NOAA station. You can see that high tide water levels are higher within the restored channel than Tacoma, this is common for Nisqually because it is situated at the bottom of the Puget Sound where tides are amplified. The flattened bottom on the restored channel data during low tides is just indicating the elevation at which the logger is placed. The dashed line represents the elevation of the marsh plain next to this logger. Using this data we can quantify how often and long the marsh plain is inundated, key pieces of information to understanding vegetation colonization and vulnerability to sea level rise.
- SEDIMENT AND GEOMORPHOLOGY – Next I’d like to talk about Sediment and Geomorphology.
- HISTORIC CHANNELS – I would first like to talk about channel development in the Refuge restoration site. Channels are the means by which tidal and freshwater are moved throughout an estuary and bring nutrients and sediment to This map shows the historic water channels in the Nisqually Delta based on data from 1878 and overlaid on an aerial photo from 2005. The dike was built a couple of decades later disconnecting the channels within the area from McAllister Creek, the Nisqually River, and Puget Sound. What is interesting to me, is that over 100 years later, you can still see the historic channel beds within the diked areas from the aerial photograph. By removing the dike, more than 21 miles of tidal sloughs and channels are being restored in the Nisqually Estuary.
- CHANNEL DEVELOPMENT – One of the uses of aerial photography is to track channel development within the restored areas. The first map on your left shows the tidal channels as they existed based on the 1878 US Coast Survey Topographic Map. Jennifer Cutler, with the Nisqually Indian Tribe, created this map and then used a 2005 aerial, shown in the middle, to digitize the tidal channels as they existed at that time. We then used the December 2009 aerial to digitize the channels after dike removal. You can see that water is flowing into the restoration area and even occupying some of the same historic channels that existed in 1878. We will use this data to also quantify channel length, width, and development by channel order.This process provides us with a tool for tracking two dimensional changes in channel development. To capture those three dimensional changes we are also using bathymetry and channel cross sections.
- BATHYMETRIC SURVEY – We completed our first bathymetric survey last summer. Bathymetry using sound waves to determine depth in water. This map does not show the results of the survey, but the areas we were able to cover. Here at the SFBE field station we use a single-beam echosounder (RESON NaviSound 210) that connects to a transducer mounted under the front of the boat.An echosounder measures the length of time it takes for a sound wave to return to the transducer after reaching the substrate. This time is analyzed to provide a measure of depth. (NOAA)
- BATHYMETRIC SURVEY – These are the results from that survey. Blue colors are low elevations (or deepest areas) and red colors are high elevation (or shallowest) areas. We found that Animal slough, which serves as a reference site and has never been diked, had the lowest average elevation, meaning it was the deepest and more developed and scoured. Shannon Slough, had the highest average elevation meaning that it was the shallowest, which makes sense because it is newly restored.
- CHANNEL CROSS SECTION – Lets look at this a little more closely using channel cross section data. This is another method for looking at three dimensional changes in channels. This graph shows the changes in channel morphology between pre dike removal conditions in 2009, shown here in pink, and conditions in 2010, shown in blue. The y-axis represents elevation in meters and the x-axis indicates the distance across the channel using the UTM coordinate system. Lets first look at the top graph which is from the Shannon middle monitoring station, shown here on the aerial photo. You can see that the channel bottom has scoured out significantly from pre-dike conditions. Changes at monitoring station Shannon south are opposite, with the channel bottom increasing in elevation during the first year. This area is much further away from mouth of the channel and its banks are not as defined, reducing water velocity and its capacity to scour. During the 100 years these channels had been diked off from tidal flow, they began to fill in and colonize with freshwater and invasive plants such as cattail and reed canarygrass. This photo of a USGS intern conducting a channel cross section survey was taken at Shannon Slough South monitoring station prior to dike removal. With tidal waters now reclaiming their historic channel beds after dike removal, this vegetation began to clear out and it is exciting to see these changes.
- SEDIMENT AND GEOMORPHOLOGY – Along with tracking the changes to the restored tidal channels, we are also looking changes in elevation on the restoring marsh plain. I’d like to focus in on two of the Tribal restoration sites, Pilot and Phase I and some of the elevation measurements we recently collected.
- ELEVATION –We are using LiDAR and bathymetric mapping to gather elevation data on a landscape level and within each study site conducting more detailed on the ground elevation mapping using a real time kinematic GPS. This provides us with centimeter level accuracy which can be very valuable when evaluating tidal marsh vegetation colonization and vulnerability to sea level rise. This map shows the Nisqually Tribe Pilot and Phase I restoration sites, which were reintroduced to tidal inundation in 1996 and 2002. Elevations were measured at each intersection of the grid shown on the map. The species of plants found at each grid intersection were also recorded.
- ELEVATION – With these known elevation points, we created a digital elevation model for these sites. High elevations are shown in reds and yellows, and low elevations in greens and blues. Channels are also displayed with elevation data from a Lidar survey conducted last winter. Elevation maps such as this one are valuable for numerous restoration and monitoring actions. They guide restoration plans and are used to help predict where certain estuarine habitats will form. We can also use these maps, along with water level logger data, to map which areas are inundated during different tide heights and also to map which areas would be inundated based on different sea level rise scenarios.
- SPECIES RICHNESS BY ELEVATION – This map shows the elevation data, along with the number of plant species found at each grid intersection. You can see that the higher elevation areas also support the highest number of plant species. This result is confirmed using correlation analysis which showed a significant correlation between elevation (along the x-axis on the bottom) and number of plant species (shown on the y-axis). This graph was created by one of our technicians, Lisa Belleveau, also a grad student at The Evergreen State College as part of her thesis work.
- ELEVATION – Lets talk a little more about the relationship between elevation and tidal marsh plants. They say that real estate is all about location, location, location. In our work, salt marsh restoration is about elevation, elevation, elevation. Because these landscapes are inundated with salt water on a daily basis, tidal marsh species have had to adapt to tolerate these conditions. However, different species have different tolerance levels. This diagram illustrates the different types of Pacific Northwest tidal wetlands based on a tidal datum. For example, eelgrass can grow in areas that are first inundated during mean lower low water tides, whereas in the high salt marsh, plants are only inundated above mean higher high water tides. The difference between these habitats can be a slight change in elevation by mere centimeters. This is why when restoring and monitoring salt marsh, we must have a good understanding of elevations at our sites.
- PLANT ELEVATION RANGES– Lets look at an example of this from Nisqually. This graph was also created by Lisa for her thesis. She graphed the elevation ranges measured for each of the species we observed. The number in parentheses represents the number of times that species was observed during surveys. As you can see there is a slight gradient with species like Spergularia and Eleocharis found at lower elevations and species like Douglas Aster and Canadian lettuce (Lactuca canadensis) found at higher elevations. You can see that some species have very narrow elevation ranges, while others have much larger ranges. This shows that slight changes in elevation can often lead to large changes in plant communities. These data can be very useful for both restoration scientists and land managers for predicting tidal marsh species colonization based on elevation.
- PLANT ELEVATION RANGES– Lets use this graph and go back to our elevation map. The locations where spergularia was observed is shown by the white dots and corresponds to lower elevations throughout these restoration sites.
- PLANT ELEVATION RANGES– Salt grass, Disticlis spicata, has a broader elevation range and a broader distribution on the restoration sites.
- PLANT ELEVATION RANGES– Jaumea carnosa, has a bit tighter elevation range and is found in medium to high elevation areas.
- PLANT ELEVATION RANGES– Finally, Grindelia, located at the upper end of our graph, was found in some of the highest elevation areas.
- VEGETATION MONITORING – So what do these data tell us about what might happen at the Refuge? Across the Delta we have permanent vegetation study sites that we measure annually. We are also measuring soil salinity and elevation at each station. As you can see from this aerial photograph taken last July, there was a lot of vegetation coming in on the Tribe Restoration sites and surrounding salt marsh, but the Refuge restoration site was looking pretty bare. This is because this area is in transition from a freshwater to estuarine habitat and much of the freshwater plants have died with the introduction of salt water.
- VEGETATION MONITORING – We are, however, starting to see some salt marsh plants already colonizing the site. On the left is a picture near the Shannon Slough North monitoring station with spergularia starting to come in near the foreground. As we saw in the previous slides and in the graph in the top right, this species grows in lower elevation marshes. Further back, on a mound of decomposing cattail roots, Grindelia has bloomed. Remember that this species tends to grow in higher elevation marshes. This is a great example that illustrates that small changes elevation, can lead to big changes in plant communities. On the right, two of our Refuge volunteers are helping with a vegetation survey on the Tribe Phase II restoration site. This site was opened up to tidal flow five years ago.
- INVASIVE SPECIES – Another benefit we have measured is the reduction in invasive reed canary grass. Invasive Reed Canary Grass dominated the Refuge landscape prior to dike removal. On the top right you can see a picture of how tall it can get. In our pre-restoration survey, we found that 62.3% of our permanent vegetation transects were covered by invasive Reed Canary Grass (Phalaris arundinacea). This summer we detected less than 1% of Reed Canary Grass on those same transects.
- We know, however, that tidal marshes are not static ecosystems, but rather dynamic ones. Elevations can increase or decrease over time through subsidence, uplift and organic and inorganic sediment inputs. As I mentioned earlier, the Nisqually Refuge restoration site has subsided over the 100 years it was diked, and now that it is again connected to tidal inundation and inputs and outputs, we can expect the elevation to change again. Eric Grossman and Chris Curran, two of our USGS partner scientists, are researching the sediment budget of the Nisqually River and specific sites on the Delta. They are studying how sediment moves down the river and if and how much is transported to the restoration site on a flood tide and how much is moved further north during an ebb tide. They have ADCP’s out on the Nisqually River, the Delta, and two restored channels in the restoration site that measure continuous current and sediment fluxes, these are denoted by the yellow triangles. They are also mapping Alder Lake, a man made reservoir on the Nisqually River, to compare to a 1940s map to measure how much sediment the dam is trapping.
- SETS – As we look at the sediment budget and movement throughout the Delta, we also are measuring how much sediment is being deposited on the tidal marshes to see if we are building or losing elevation, and at what rate. Surface Elevation Tables, commonly know as SETs are a method used to mechanically measure precise changes in surface elevation. This data extends beyond the boundaries of the Nisqually Estuary and is also being used in part of a national climate change study which is looking at the vulnerability of tidal marshes to sea level rise led by Glenn Guntenspergen with the USGS Patuxent Research Center.
- SET RESULTS - This graph displays the average change in elevation in millimeters at three of our study sites from pre-dike removal in the Summer 2009 to Summer 2010 and ending with Spring 2011. You can see that sedimentation accumulation at the Refuge was relatively large during the first year after dike removal in comparison to the Phase II restoration site and Reference marsh. On average, we measured about 37 mm or 3.7 cm of sediment accumulation throughout the Refuge. Between Summer 2010 and this past spring, however, we only measured on average, an additional 8 mm of sediment accumulation.Higher sediment deposition rates measured at the Refuge may be the result of multiple factors. The Refuge restoration area is generally lower in elevation than the surrounding study sites due to a lack of sediment inputs from the Nisqually River and Puget Sound over the 100 years it was diked. This means that this area is now inundated more often and for longer periods of time during a tidal cycle, thus exposing it more frequently to sediment rich waters. There has also been a lot of construction work at the Refuge with the dike removal and some of this sedimentation may be from local movement of loose soils, especially seen during the first year.
- SUBSTRATE COMPOSITION – We are not only looking at sediment accumulation rates, but also the composition of the sediment or substrate throughout the Delta. This map shows substrate composition throughout the Delta in 2009 prior to dike removal as part of our offshore to onshore study with Eric Grossman, Chris Curran, and Steve Rubin. In general, the Delta front tended to have a higher percent of sand making up substrate composition while the area just north of the dike had a higher percentage of silt. This makes sense as the dike was acting like a dam, and was building up silt behind it.
- Sediment also provides habitat for benthic invertebrates and the type and composition can influence invertebrate communities. This map shows the benthic invertebrate composition in the same locations where substrate was analyzed in the previous slide. These data show that prior to dike removal in 2009, tidally influenced sites were dominated by polychaetes, a class of marine annelids (segmented worms), while the diked Refuge restoration site was dominated by arthropods, primarily Dipteran (or fly) larvae. These data suggest that with tidal influence, there will be a shift in the benthic invertebrate community composition towards more estuarine and marine taxa such as polychaetes and crustaceans.
- 2010 PRELIMINARY RESULTS – We only have a few samples processed from 2010, but they are indicating so far that we are transitioning to more estuarine benthic communities with
- BIRD SURVEYS - We conduct monthly area bird surveys at four restoration sites and our reference marsh. In addition to recording species, number, behavior and habitat, we also place the location of each bird in a 250 or 100 m grid depending on the site. For the Refuge, were are surveying all the areas within the footprint of the old dike as well as the enhanced freshwater wetland. The bulls-eyes on the map represent locations of our spring point count surveys.
- BIRD ABUNDANCE: This is a graph showing total number of birds by foraging guild observed each month. So far, the trends we are seeing seem to be driven by seasonal and migratory patterns as shown by the influx of dabblers and geese during the fall and winter. Please note that only one pre-restoration survey is shown on this graph. One of our technicians and Evergeen grad student, Heather Tucker, is working on compiling more pre-restoration bird survey data conducted by the Refuge so that we have a better understanding of pre-restoration conditions. This with multiple years of post-dike removal data will allow us to better explain the effects restoration actions have had on avian communities.
- BIRD DENSITY MAP – Another way we are exploring our monthly bird survey data is by adding a spatial component. Because we use a grid system to record where each bird is observed, we can map bird observations on a finer scale than just by study site. This map is showing total bird densities throughout the Nisqually Delta for Fall 2009. Cool colors indicate low densities and warm colors indicate high densities. You can see our five study sites on the map and also the managed freshwater wetland within the Nisqually NWR, outlined in yellow. We created these maps for each season last year to see how bird densities changed spatially. Overall, densities were evenly distributed throughout the Nisqually delta with some higher densities in the freshwater wetland, Reference marsh and Tribal restoration sites.
- DIKE REMOVAL – Here is a photograph from the dike removal this summer. This shot was taken along the northern dike. The Sound is on your right to the north and the Refuge is to the left. I can tell you that trying to collect baseline monitoring data this summer while all this was going on was pretty exciting. Huge trucks full of dirt were driving everywhere, access was frequently blocked by excavators, and I literally had to turn around at times because the dike I used to drive on had been removed.LETTING THE TIDES IN – On September 23th of this year, the first Puget Sound tides entered the Nisqually NWR site in over 100 years. This picture is of Steve Liske, the Ducks Unlimited engineer for the project, standing on the last piece of dike separating the Sound on the right, to the freshwater inside the restoration site on the left. When the tide was high enough, an excavator removed the sliver of land and we were able to witness the waters mix.PROJECT PARTNERS – First, I wanted to acknowledge our project partners. The Nisqually Delta is a dynamic region that has attracted many researchers and we are proud to be coordinating research with many of them. I’d specifically like to recognize our partnerships with the Nisqually NWR, Nisqually Indian Tribe, Ducks Unlimited, USGS Coastal Marine Geology, USGS Western Fisheries Research Center and the Nisqually River Foundation.