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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 Results from a Pilot Study. A Multi-Partner Research Project.
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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 SpringSome 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)
Dive-in Funnel opening below water level 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
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
Bluebill Tracker on DU Website: http://www.ducks.org/scaupstudy