shorebird project overview - ut forestry wildlife...

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Tennessee Valley Shorebird Assessment Project

SHOREBIRD CONSERVATION AND MONITORING


RESOURCES

US SHOREBIRD CONSERVATOIN PLAN http://www.fws.gov/shorebirdplan

WATERFOWL MANAGEMENT HANDBOOK -http://www.nwrc.usgs.gov/wdb/pub/wmh/contents.html

MANOMET CENTER FOR CONSERVATION SCIENCEShttp://www.manomet.org/ & http://www.shorebirdworld.org

International Shorebird Survey (ISS)– Migratory Only

Program for Regional and International Shorebird Montiroting (PRISM) – Breeding and Migratory

Western Hemisphere Shorebird Preserve Network(WHSRN) – Significant Breeding and Migratory Stop- over Sites


OVERVIEW

• INTRODUCTION TO SHOREBIRDS

• MANAGEMENT FOR SHOREBIRDS

• TVA REGIONAL SHOREBIRD PROJECT

• ESTIMATING SHOREBIRD NUMBERS

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WHAT ARE SHOREBIRDS?

• Sandpipers• Dowitchers• Plovers• Oystercatchers• Avocets• Stilts

Painting by James Coe

214 SPECIES WORLDWIDE50 REGULARLY OCCUR IN U.S.31 OCCUR IN TN RIVER VALLEY


MIGRATORY SPECIES

RED KNOT20,000 MILES IN 1 YEAR

BAR-TAILED GODWIT6,000 MILES NON-STOP


NICHE PARTITIONING

VARING BILL SHAPES AND LENGTHSALLOW MULTIPLE SPECIES TO FORAGEIN SAME AREA

AMERICAN GOLDEN PLOVER

AVOCET

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EXAMPLES OF SHOREBIRDS IN TN RIVER VALLEY

KILLDEER GLEANS PREY FROM MUD TO UPLAND ZONES


BLACK-BELLIED PLOVERSIMILAR FORAGING STRATEGY AS KILLDEER


PECTORAL SANDPIPERFORAGES WITHIN VEGETATION AND MUD ZONE INCLUDINGVERY SHALLOW WATER

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GREATER YELLOWLEGSPRIMARILY FORAGES IN WATER


SNIPESHALLOW WATER AND MUD ZONE, OFTEN AROUND VEGETATION


SHORT-BILLED DOWITCHERWADES IN DEEPER WATER, NOTE LONG BILL

DUNLIN

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MANAGEMENT OF SHOREBIRD HABITAT-BREEDING

PROMOTE NATIVE GRASSLANDS – SHOREBIRDS PREFER TO NEST IN GRASSLAND HABITATS. USE OF THESE HABITATS VARIES BY SPECIES, SOME (AVOCETS) PREFER SPARSELY VEGETATED HABITATS. OTHER SPECIES (UPLAND SANDPIPER) PREFER GRASSLANDS WITH MORE VERTICAL STRUCTURE.

PRESCRIBED BURNING - A USEFUL TOOL FOR DEVELOPING SHOREBIRD NESTING HABITAT.

ESTABLISH BREEDING SITES NEAR FOOD SOURCE – NECESSARY FOR MOST SPECIES, ALTHOUGH NOT NEEDED FOR PLOVERS, AS THEY ACTIVELYFEED IN VEGETATIVE ZONE.

RED KNOT


MANAGEMENT FOR SHOREBIRDS - MIGRATION

MOIST MUD FLAT HABITAT WITH <20% VEGETATIVE COVER

SHALLOW WATER <20 CM DEEP

LARGER FLATS ARE BETTER – REDUCES IMPACTS FROM DISTURBANCES.

TIMING IS CRITICAL - HABITAT MUST BE AVAILABLE WHEN BIRDS ARE PASSING THROUGH. MIGRATORY PERIOD BEGINS MID-JULY-OCTOBER, ADULTS MOVE THROUGH AREA BEFORE JUVENILES. ALSO PROVIDE HABITAT FOR WINTERING SPECIES (DUNLIN, LEAST SANDPIPERS).

MANAGED SUB-IMPOUNDMENTS – SHOULD BE DRY IN SUMMER, DISK VEGETATION, FILL AND SLOWLY DRAIN. EXOTIC VEGETATION CAN BE PROBLEMATIC.


HOW DID TVA GET INVOLVED WITH SHOREBIRDS?

TVA’S RIVER OPERATION STUDY

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Regional Assessment and Management of Inland Stopover Habitats for Shorebirds in the Tennessee Valley


Tennessee Valley Authority

Tennessee Wildlife Resources Agency

U.S. Fish and Wildlife Service

Kentucky Department of Fish and Wildlife Resources

Alabama Department of Conservation and Natural Resources

University of Tennessee, Knoxville

US Army Corps of Engineers

Partnerships


Overview

Construction of TVA dams over the past 60+ years has created extensive inland mudflat habitats in the Tennessee river valley through fall drawdown of the reservoir system

There have been several major changes in the way TVA manages fall drawdown:

•1970’s, 1980’s saw major changes system wide

•Other, smaller-scale changes on individual reservoirs

•Latest change: Reservoir Operations Study (ROS), an extensive study of environmental impacts caused by different reservoir management scenarios

•One area of special concern in the ROS was the impact of extended summer reservoir levels, delaying the creation of mudflat habitats used by migrating shorebirds.

There has never been a valley-wide, systematic study of shorebird habitat use. No evidence that any of the past reservoir management scenarios has been optimal for creating shorebird habitat.

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Project Goals

As part of the ROS record of decision, TVA will fund a 5 year study of shorebird resources across the Tennessee River Valley. Primary objectives of the study:

•What shorebird species migrate through the valley, and in what numbers?

•When do they migrate through? Look at individual species and total number of individuals in all species.

•Where do shorebirds stopover in the valley? Do mudflats on TVA managed reservoirs play a key role in long-term migration stability?

•How does TVA management of the river system affect stopover habitats?

Can we identify an ideal river management scenario that provides the best combination of timing and extent of habitat availability?

Key point: Although we are tasked with assessing management impacts of ROS, the scientists involved in the study are most interested in an overall assessment of shorebird resources both on and off TVA lands, in cooperation with other state and federal agencies and public interest groups.


Tennessee River Valley

•TVA manages 9 mainstem reservoirs and 40 tributary reservoirs.

•Multiple use management system.

•Tributary reservoirs provide little habitat due to local geomorphology—steep sided, deep lakes with few mudflats.

•Mainstem reservoirs are shallow and provide a lot of habitat. Of these Kentucky and Wheeler reservoirs encompass the most. Douglas and Chickamauga provide key habitat in the eastern valley.


Reservoir Operations StudyFive year study to examine all aspects of TVA’s management of the Tennessee River System. ROS results guide daily management of the river system.

•Multiple use: Navigation, flood control, power production, recreation, resource conservation.

•Key public concern was to keep docks and marinas open through Labor Day. Extension of summer pool was accepted on some reservoirs, rejected on others.

•No change on Kentucky lake, which has a majority of valley shorebird habitat. Changes in the 1990s were evaluated by TVA and other agencies, and determined harmful to habitat and flood control.

•River Operations Group continues to evaluate ROS. Our study will provide valuable information on shorebird habitats and timing, and help make better decisions.

ROS is an adaptive management plan.

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Changes in reservoir levels under ROS

Kentucky Lake

Wheeler Lake

Mudflats Start

Lots of Mudflats


Chickamauga Lake

Douglas Lake

Changes in reservoir levels under ROS


International Shorebird Survey protocol:

•Survey sites each third of the month starting in July and ending in October

•Conduct surveys throughout the valley on the same day as weather and logistics permit

•Alternative guidelines for less intensively monitored sites. Monitoring by agencies on key sites, citizen scientists on other sites

•Periodic monitoring to gauge overwintering possibilities.

Regional habitat assessment

•Collaborative effort, with TVA helping to organize surveys identify areas to monitor.

•May 2005: first regional meeting with TVA, TWRA, USFWS, KYFWS and other interested parties to begin organizing this valley-wide effort. Other, regional meetings to follow. Includes identification workshops, protocol review, identification of habitats.

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Techniques to identify and assess key habitats

•Expert opinion captured as valley-wide map series, identifying both on and off reservoir habitats

•Historic maps showing pre-impoundment elevations to highlight locations where unknown mudflats may exist

•Cooperative work with Corps of Engineers for bathymetry and aerial photography

•LIDAR and aerial photography on key flats to quantify mudflat availability at different reservoir levels

•Vegetation study to quantify habitat suitability for overwintering waterfowl


Habitat Mapping


Habitat Mapping

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How much habitat

•A critical question is how much exposed mudflat is required to support the number of birds migrating through at any given time

•Trying to identify the best scenario to provide ideal habitat to the highest number of birds and species: When is habitat exposed, and how much is exposed at any given elevation? Is this best for birds?


LIght Detection and Ranging (LIDAR)

• Laser Data Acquisition Technology • Airborne system for rapid coverage of difficult terrain and applications• Laser points are positioned by highly accurate GPS and Inertial Measurement System • Produce very precise digital elevation models (DEMs) •Acquires 15,000 points per second , 1 point every square meter on the ground•Typical vertical accuracy + 4-6 inches•Typical horizontal accuracy + 12-30 inches


Systematic Shorebird Surveys

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Reservoir Level 990


Reservoir Level 987


Reservoir Level 985

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Reservoir Level 983


Reservoir Level 980


Reservoir Level 975

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Reservoir Level 970


Historic Patterns & Citizen scientistsAugust

(n=2465 birds, 19 visits)

Killdeer27.1%

Ot her2.8%

Pect oral Sandpiper

Peeps33.7%

Lesser Yellowlegs7.0%

Semipalmat ed Plover

1.5%

Spot t ed Sandpiper

2.0%

Solit ary Sandpiper

3.4%

Great er Yel lowlegs

2.3%

Dunl in0.0%

September(n=1552 birds, 14 visits)

Killdeer34.2%

Other5.2%

Peeps38.1%

Lesser Yellow legs

3.0%

Semipalmated Plover

6.7%

Spotted Sandpiper

1.1%

Solitary Sandpiper

0.2% Greater Yellow legs

0.5%

Pectoral Sandpiper

11.1%

October(n=544 birds, 9 visits)

Killdeer34.6%

Lesser Yellow legs

1.5%

Spotted Sandpiper

0.4%

Solitary Sandpiper

0.2%

Greater Yellow legs

0.9%

Dunlin43.4%

Pectoral Sandpiper

7.5%Other0.4%

Peeps11.2%

November(n=1756 birds, 7 visits)

Dunlin81.0%

Great er Yellowlegs

1.8%

Solit ary Sandpiper

0.1%

Lesser Yellowlegs0.2%

Killdeer12.9%

Peeps3.0%

Pect oral Sandpiper

0.6%

Other0.5%

December(n=166 birds, 2 visits)

Killdeer77.1%

Pectoral Sandpiper

0.6%

Peeps22.3%


Migration Timing

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Migration Timing


University studies

TVA is funding university studies on specific habitat questions:

•University of Tennessee, Department of Geography: role of mudflat shape and reservoir level in creating mudflat habitats during fall migration.

•University of Tennessee, Department of Forestry, Wildlife and Fisheries: waterbird use of mudflats in east Tennessee. Examining vegetation development, abundance of invertebrates, and seasonaluse of flats by shorebirds and waterfowl.

Other studies as funding and needs warrant:

•Similar waterbird study in west TN.


What have we learned?

1. Historical shorebird data does not adequately depict presence ofspecies throughout fall migration. We need data to be acquiredsystematically, throughout migratory period.

2. Approximately 150 mud flats exist throughout the Valley, only a fraction provide optimal habitat for shorebirds.

3. Delaying drawdown results in an overall reduction in vegetative biomass and species diversity.

4. Reservoir drawdown should be slow and steady, dramatic drawdownsresult in poorly developed vegetative communities; limiting the establishment of moist soil species.

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Questions?

Contact information:

Roger Tankersley, Jr.: GIS and habitat assessment

<[email protected]>

Travis H. (Hill) Henry: Shorebird monitoring

<[email protected]>

Michael Roedel: Tennessee Wildlife Resources Agency

<[email protected]>


APPLICATION OF DRAWDOWN MODEL

A MODEL TO DETERMINE SHOREBIRD HABITAT AVAILABILITY UNDER

DIFFERENT DRAWDOWN REGIMES.

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