Harlequin Ducks in Idaho Ecology, Distribution, Monitoring & Conservation

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1 Paul Higgins Harlequin Ducks in Idaho Ecology, Distribution, Monitoring & Conservation Sonya Knetter & Frances Cassirer, IDFG Jacob Briggs, BYU-Idaho Idaho Bird Conservation Partnership, March 12, 2015

2 Outline Overview: Life History & Ecology Distribution, Abundance, and Trends Threats Conservation Needs Assessment

3 Annual Life Cycle Sea duck winters in surf along northern rocky shorelines Pair bonds formed on wintering grounds Migrates inland to breed

4 Annual Life Cycle Arrive on breeding streams in April through early June Swiftly-flowing mountain streams clear streams 10m or wider cobble or boulder substrate streambank with trees, shrubs, or tree/shrub mosaic mature overstory away (50m) from roads Nest near water, often upstream of breeding pair activity on ground, rocky crevices, cliff ledges, woody debris, hollow trees or snags in adjacent forest Sonya Knetter Clay Hayes

5 Annual Life Cycle Males depart for coast when female begins incubating clutch of 5-6 eggs; precludes renesting 28 days incubation, average 49 days to fledging Brood habitat young broods use narrower, meandering upstream reaches with slower water (lower gradient), more loafing sites. Move downstream over the summer. Female and ducklings leave in August and September for coast to winter and molt Pairs reunite on wintering grounds Meet where we dined on those good clams? Earlier in spring Kris Hennings, USFS

6 Movements & Migration In western North America, movements based on Band returns Recaptures Observations

7 Life History Traits Long-lived Low reproductive output John Crawley Delayed reproduction. Females first breed between 2-5 years of age High rate of nonbreeding. Varies with environmental conditions, especially food abundance Philopatric. Females likely return to natal streams to breed, site fidelity to breeding, molting and wintering areas Lifetime pair bond. If female does not reunite with male on wintering grounds, male may return alone to stream the following year.

8 Conservation Concern Limited distribution and small population size Breeding: Species of Greatest Conservation Need ID, WY (Tier 2), Species of Concern (MT) Game species managed under state and federal migratory waterfowl regulations cooperatively through the Pacific Flyway Council Subject to harvest primarily on coast; limited opportunities for sea duck harvest. In general, monitoring programs exist on wintering grounds, but there is recognition that for sea ducks they are not as accurate as desired Better and/or sustained monitoring needed on both breeding and wintering grounds

9 Distribution and abundance Global population~230,000 Iceland ~ 14,000 Greenland ~ 2,000+ Atlantic NA population ~ 1-2,000 ESA petitioned but not listed Hunting season closed 1990 s Chronic oiling and misidentification by hunters remain threats Pacific NA ~ 165,000 Pacific Asia ~ 50,000+

10 Distribution and abundance western US population ~1000+ STATE ESTIMATED NUMBER OF BREEDING PAIRS Washington 275 Montana 110 Idaho 50 Oregon 40 Wyoming 40 California 0 Colorado 0 TOTAL 515

11 Idaho Distribution, abundance, and trends: methods : collect historical info, conduct statewide surveys (IDFG, USFS) : research and monitoring (NGEO) 1996: Harlequin duck conservation assessment and strategy for the U.S. Rocky Mountains, monitoring plan for ID, MT, WY : annual to periodic monitoring of selected streams (USFS, IDFG) : intensive surveys in northern Idaho (SWG,IDFG) : annual to periodic monitoring of selected streams

12 Idaho harlequin duck breeding distribution 13 Breeding occurrences Containing 24 streams Northern Idaho (WA) Southeastern Idaho (WY)

13 Breeding occurrence Drainages or portions of drainages used by harlequin ducks where breeding is known, i.e. a brood or nest has been observed within the last 15 years. Comprised of contiguous stream reaches (and portions of lakes, reservoirs, or bays) used during the courtship, nesting, and brood-rearing periods.

14 Harlequin duck surveys: Timing is everything!

15 Bellwether Survey Design Sampling with partial replacement allows collection of precise information on trend at fixed sites (bellwether streams) while also periodically sampling (via rotational streams) the entire population of interest. Eight bellwether and 16 rotational streams in Idaho. Originally designed for the 3 Rocky Mountain States to implement collaboratively.

16 Population index estimation Population size = Σ Pairs observed on bellwether streams + Average number observed on rotational streams X Total number rotational streams surveyed Variance Derived from the variance on the rotational streams.

17 Number of pairs Idaho Population Estimate pairs pairs

18 2007 Harlequin Duck Surveys $37K State Wildlife Grant matched by IDFG nongame program Objectives Quantitatively reassess the distribution and abundance of harlequin ducks breeding in Idaho Evaluate the utility of aerial surveys for census

19 Number of streams Harlequin duck occupancy ( ) of 30 streams by breeding status (<=1996) Brood Adults None 0 Confirmed Unconfirmed Potential, but no detections Breeding status as of 1996

20 Number of pairs Idaho Population Estimate pairs 41 pairs

21 Summary of population trend No significant population change detected: No ducks seen in 2007 on three previously confirmed breeding streams (St Joe, Granite Creek (Pend Oreille), Moyie) but in 2011 and 2012, multiple females with broods on the St Joe River Brood observed on one stream where only adults had previously been reported (Two Mouth Creek) Documented new breeding stream (Cow Creek) tributary to stream with confirmed breeding No breeding observed in eastern Idaho (Pahsimeroi) Possible declines on several streams since 2007

22 Maximum no. pairs observed Lochsa River

23 Maximum no. pairs observed Big Elk Creek

24 Eastern Idaho Observations Local Harvest Human Disturbance Yellowstone Observations

25 Threats Water flow (flash flooding, dewatering) Water quality (sedimentation) Pollution (hydrocarbons, heavy metals) Loss of riparian vegetation (loss of nesting habitat, predation) Disturbance (instream and adjacent)

26 Harvest Harlequin duck hunt, Aleutians No specific protection for harlequin ducks in Idaho Few are present during waterfowl season, limited incidental harvest (reporting not required) Both Washington and British Columbia have imposed restrictions due to conservation concern (at-risk or sensitive) in other jurisdictions WA 1 bird per season, mandatory report ~190 harlequins harvested annually (7%), extensive annual surveys indicate relatively stable wintering population of harlequin ducks in greater Puget Sound (~2,700 birds) BC 2 per day, 6 in possession No special seasons in Oregon (7 ducks daily bag, sea duck permit required). Alaska 6 per day, 12 in possession.

27 Conservation Needs Systematic monitoring and data management Survival and movements data Coordination with adjacent breeding area jurisdictions (Washington, Wyoming, Montana, Alberta) Coordination with wintering area jurisdictions (especially Washington and British Columbia) Paul Higgins Sonya Knetter Keith Carlson

28 Acknowledgments IDFG Regional Staff Joel Sauder Beth Waterbury Numerous field staff! Conservation Partners Dedicated volunteers!