DISTRIBUTION AND ABUNDANCE OF SEA DUCKS AND DIVING DUCKS ON LAKE ST. CLAIR AND W. LAKE ERIE

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1 DISTRIBUTION AND ABUNDANCE OF SEA DUCKS AND DIVING DUCKS ON LAKE ST. CLAIR AND W. LAKE ERIE Dave Luukkonen, Michigan DNR and Michigan State University

2 Importance of Lake St. Clair and western Lake Erie Areas of continental significance for migratory birds ú N.A. Waterfowl Management Plan 2004 and 2012 Priority area/species for monitoring and conservation during migration ú UMRGLR Joint Venture ú State wildlife action plans ú EPA: Detroit River-Western Lake Erie Basin Indicator Project Multiple ecosystem stressors potentially affecting birds ú Invasive species (e.g., zebra and quagga mussels) ú Boating and other human disturbances ú Shore and offshore developments (e.g., wind energy) ú Water quality ú Climate change

3 Historic Pelagic Bird Monitoring U.S. Lake St. Clair only Zebra Mussel Distribution

4 Historic Changes in Canvasback and Scaup Abundances on Lake St. Clair Approximate doubling of diving duck use-days in U.S. waters ú Luukkonen et al Impacts of Dreissenid mussels on the distribution and abundance of diving ducks on Lake St. Clair. Pages in T. R. Nalepa and D. W. Schloessor, eds., Quagga and Zebra Mussels: Biology, Impact, and Control 2 nd Edition. Fall duck use-days / year ( +95% CI) 1,400,000 1,200,000 1,000, , , , , (Pre-dreissenid) (Post-invasion) Canvasback Scaup Redhead

5 Historic and Current Pelagic Bird Monitoring U.S. Lake St. Clair only , Current Lake St. Clair & W. Lake Erie

6 Coordinated Pelagic and Near shore Bird Monitoring Objectives, Fall , present : Diving ducks studies only : Fall, winter, and spring distributions and abundances of birds: Diving ducks, Dabbling ducks,sea ducks Tundra and mute swans Gulls Bald Eagles Year Oct Nov Dec Jan Feb Mar Apr May Jun Total Total Model bird distributions based on lake characteristics and human disturbance

7 DISTANCE SAMPLING METHODS Systematic line transect survey with a random start point spaced at 3.2 km (2 mile) intervals: 26 primary and 24 alternate transects Target altitude and speed: 300 ft and 90 mph Georeferenced detections collected in 5 distance intervals Estimation of detection probabilities, population size, and duck use-days based on Multiple Covariate Distance Sampling accounting for flock size: ú Shirkey et al Application of distance sampling techniques for diving ducks on Lake St. Clair and western Lake Erie. J. Great Lakes Res. 40: Distributions characterized using the kernel density estimator applied to observation locations on transect lines.

8 Seasonal Diving Duck Abundance Estimates Based on Distance Sampling Methodology, Lake St. Clair, Detroit River and western Lake Erie, ,000 Diving duck population estimate 600, , , , , ,000 Autumn (15 Oct - 31 Dec) Winter (1 Jan - 28 Feb) Spring (1 Mar - 7 May) Days from 1 October

9 Relative Abundance and Composition of Waterfowl Observed on Lake St. Clair, Detroit River and western Lake Erie, Mean number observed per survey Percent of observations 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Relative Abundance by Taxonomic Group Dabbling ducks Diving ducks Sea ducks Ruddy ducks Jan Feb Mar Apr May Jun Oct Nov Dec Composition by Taxonomic Group Jan Feb Mar Apr May Jun Oct Nov Dec

10 Sea Duck Species Composition in U.S. Waters of Lake St. Clair (Fall) and Entire Study Area U.S. Waters Lake St. Clair, Fall Entire Study Area, Fall, Winter, Spring MERGANSERS BUFF MIXED COGO LTDU WWSC MERGANSERS BUFF MIXED COGO LTDU WWSC

11 Seasonal Sea Duck Distributions, and

12 Sea Duck and Diving Duck Distributions, Winter 2013

13 Continental and/or Regional Significance for Migratory Birds Avian use-days (2012) 30,000,000 25,000,000 20,000,000 15,000,000 10,000,000 5,000,000 0 Winter Fall Diving Ducks Peak populations during fall migration 600,000 diving ducks 22.5 million diving duck usedays Approximately 21% of the diving duck use-days in the Upper Mississippi River and Great Lakes Joint Venture region.

14 Dabbling Ducks Peak populations during fall migration 123,000 dabbling ducks 3.9 million dabbling duck use- days Mergansers Peak populations during winter 38,200 mergansers 1.8 million merganser use-days

15 Swans Gulls Peak populations during fall migration 23,400 swans 0.9 million swan use-days Peak populations during winter 10,000 gulls 827,000 gull use-days

16 Predicting Diving Duck Presence/absence with Hierarchical Spatial Models Fall ( ) Spring ( ) Parameter Bˆ Bˆ Intercept Boat presence/absence Distance to shore Water depth Submerged plant diversity

17 Linkages Among Dreissenids, Disturbance, and Historic Fall Diving Duck Distribution and Abundance Disturbance Change to a food-rich system resulting in reduced tolerance for risk Scaup Canvasbacks Redheads Dreissenids SAV? Water Clarity

18 Nocturnal (FLIR) Survey (November 2010) Illustrates a much different distribution than what was observed during diurnal surveys (near-shore and Anchor Bay) Matches anecdotal evidence from duck hunters reporting large pre-dawn flights of diving ducks leaving the relatively shallow waters of Anchor Bay for open water on the main lake

19 Challenges for Balancing Benefits of Habitat and Offshore Wind Energy in the Great Lakes Protecting bird hot spots based on aerial surveys may fall short of accomplishing conservation objectives International borders and differences in regulatory frameworks Estimating economic value of potential habitat loss Public perception of wind as green energy

20 Acknowledgements Aerial survey services of Northwoods Aviation, LLC Michigan State Police, Aviation Section for FLIR flights MIDNR, USFWS, Great Lakes Commission, SCI Michigan Committee for funding