Chronology and Rates of Migratory Movements, Migration Corridors and Habitats Used, and Breeding

and Wintering Area Affiliations of Female Lesser Scaup Stopping-over on Pool 19 of the Mississippi

River in Spring

Some Preliminary Resultsfrom a Pilot Study

A Multi-Partner Research Project

Photo by Fred Greenslade

STUDY PARTNERS:

• Upper Mississippi River and Great Lakes Joint Venture• Prairie Pothole Joint Venture• U. S. Fish and Wildlife Service, Region 3• Minnesota Department of Natural Resources• USGS-Louisiana Cooperative Fish and Wildlife Research Unit• Louisiana State University• Louisiana Department of Wildlife and Fisheries• University of Illinois College of Veterinary Medicine• USGS-Northern Prairie Wildlife Research Center• Iowa Department of Natural Resources• Illinois Department of Natural Resources• Ducks Unlimited Inc.• North Dakota Game and Fish Department• Long Point Waterfowl and Wetlands Research Fund• Kibbe Research Station of Western Illinois University• Ontario Ministry of Natural Resources• Missouri Department of Conservation• Des Moines County Conservation Board• Louisa County Conservation Board• Tri Oak Foods• Mississippi Valley Calling Association

Major Hypotheses for Scaup Population Decline:

• Decreased quality and quantity of food resources on winter and spring migration areas (H1)

• Accumulation of contaminants (H2)

• Climate and habitat changes on boreal forest breeding areas (H3)

Hypotheses for Scaup Population Decline:

• All 3 major hypotheses may be directly or indirectly affecting female survival or recruitment

• Hunting probably has not been a factor in the population decline, given low harvest rates and a recent band analysis that found no relationship between harvest rates and annual survival probabilities since the 1950s (Nicolai et al. 2006)

• H1 has been formalized as the Spring Condition Hypothesis and is a focus of this Pilot Study

This Pilot Study:

• Is a follow up to previous research of scaup on Pool 19 (by Mike Anteau and Al Afton at LSU).

• They previously color-marked scaup on Pool 19 in 2004 (spray paint) and 2005 (nasal saddles), but obtained too few re-sightings of marked birds to answer research questions of interest

• Thus, satellite radios were tested in a sample of females in spring 2007

Objective 1:

Document migration corridors and affiliations to breeding and wintering areas of females stopping-over on Pool 19 during spring

- To help identify and prioritize regions and areas for habitat conservation and management

- To provide new information concerning the links and importance of Pool 19 to females utilizing various breeding and wintering areas in North America

Objective 2: Document migration chronology and estimate rate of movement (km/day) and flight distances (km) from Pool 19 to individual breeding sites

- Further test the Spring Condition Hypothesis as a potential cause of the scaup population decline

- Determine relative importance of stopover areas in the Upper-Midwest for accumulation of nutrient reserves used for breeding

Objective 3:

Identify specific lakes and large wetlands used by migrating females after departure from Pool 19

-To allow subsequent quantitative analyses of habitat use across a large landscape

- To provide guidance to managers for acquisition, protection, and management of important migration habitats in the Upper-Midwest

Objective 4:

Band a large sample (>2000) of lesser scaup

-To support and encourage subsequent annual operational bandings on Pool 19

- To provide opportunity for direct estimates of harvest rate and survival using new band analysis techniques (Nicolai et al. 2006)

Funnel opening below water level

Dive-in

Capture Methods:

• We used dive-in traps developed by IL DNR personnel

Capture Methods:• Traps were checked/emptied 2 to 3 times a day

– Mid morning– Afternoon– Just before dark

Bird Handling:

• Scaup were placed in holding pens

Bird Handling:

• Leg Banded

Bird Handling:

• Body mass was recorded

Implantation of PTTs• Surgeries by Dr. Mark Mitchell, U of IL

Preliminary Results

Banding

• We banded, weighed, and released 2482 Lesser Scaup in March 2007

• 309 females and 2173 males

Recaptures

• We recaptured and released 6 male lesser scaup that were banded and nasal-saddled on Pool 19 in March 2005

• We recaptured and released 196 lesser scaup that had been banded during this pilot study

• No foreign recaptures

17 Females Implanted with PTTs

• 14 females subsequently migrated from Pool 19

• 2 females died on Pool 19 (3 and 27 days after release)

• 1 female’s PTT failed on Pool 19

14 Females Migrated from Pool 19• 12 (86%) took a northwesterly overland tract• 2 (14%) took a northerly tract• 11 females arrived on breeding sites• 3 females died in migration (40, 45 and 52 days

after release)• 3 females died after arrival on breeding sites (78,

82 and 163 days after release)• 2 females’ PTTs failed after arrival on breeding

sites• 6 females remain alive for monitoring during fall

migration

14 Females Migrated from Pool 19

Migration Parameter

Mean Min Max

Departure Date

22 April 10 April 5 May

Days spent on Pool 19

25.6 13 40

11 Females Arrived on Breeding Sites

Migration Parameter

Mean Min Max

Arrival date 25 May 13 May 9 June

No. of Stops 6.2 2 11

Total distance (km)

3018.5 1860 4345

Days in route 34.1 24 51

Movement rate (km/day)

89.3 68.6 112.0

Bluebill Tracker on DU Website:

http://www.ducks.org/scaupstudy