April 2005
Satellite-Telemetry Project
During 2003-04 and 2004-05 waterfowl project personnel cooperated with staff of New York Cooperative Fish and Wildlife Research Unit at Cornell University placing satellite-telemetry transmitters on SC wintering Northern pintails and mallards. Following successful project results during the pilot year (2002-03) in SC the project was expanded to 5 additional AF states in 2004-05. Cooperating state and Federal personnel coordinated trapping techniques, satellite transmitter attachment, project protocol and practiced attaching transmitters to captive-reared Northern pintails. A total of 41 transmitters (NC-15, SC-10, NJ-6, MD-4, VA-3, FL-3) were to be deployed in February 2004.
South Carolina Northern Pintails
DNR personnel targeted Northern pintails at trapping sites in cooperation with Federal personnel and private landowners. A total of 8 hen Northern pintails were captured at various SC wintering sites and fitted with satellite transmitters in February 2004. Seven of the 8 birds began spring migration. The exception was the lightest in weight of the 8 pintails marked, as it remained at its release site (SCR) until its signal was lost in mid-April. Migration of the remaining 7 Northern pintails was similar to the birds marked in 2003. The birds departed SC by late March as 5 marked birds were then in Ohio and Indiana, with the other 2 birds in New York east of Lake Ontario. By the end of April, 1 Northern pintail reached the upper border of North Dakota and Minnesota, and 2 other birds were in eastern Minnesota. One bird remained on Lake Erie, and the other 2 Northern pintails staged along the St. Lawrence River in eastern Canada. Contact was lost with the remaining duck in Ohio in late March. As spring progressed, marked Northern pintails spread out across northern Canada before converging on Hudson Bay. The exception was a bird continuing northeast settling into Labrador before contact was lost in July. An additional bird was lost during May in eastern Minnesota.
In 2004 each transmitter included a UHF mortality sensor permitting researchers to locate immobile transmitters and allowing them to be refurbished and re-used. Cooperating state personnel found some transmitters previously attached to birds that died before migration. Personnel from Minnesota DNR located a transmitter from a SC instrumented bird, but the cause of mortality could not be determined.
Four Northern pintails were on the southwest coast of Hudson Bay in June, 2 via a route from James Bay, and the other 2 after departing prairie habitat and over-flying the Ontario boreal forest. In mid-summer 3 of the 4 Northern pintails remained along coastal Hudson Bay, spread from Ontario through Manitoba and as far north as Nunavut. The fourth bird departed Hudson Bay flying to North Dakota. One bird was lost in late July along coastal Hudson Bay in Ontario.
The remaining 3 Northern pintails were stationary until October when 1 departed Hudson Bay, and was shot at Saginaw Bay, Michigan in mid-October; the transmitter from this bird was returned to Cornell University with no report of anything unusual about the bird. Contact was lost with the second bird during the last week of October in Ontario south of James Bay. Coincidentally, contact was lost with 2 birds marked during the pilot project at the same time of year and region. The third Northern pintail moved to southern Minnesota by the first week of November where it was later harvested that week.
Transmitters weighing 20 grams have a 1-year battery allowing a surviving winter marked Northern pintail to be tracked through spring migration and the following fall migration back to the wintering grounds. One bird from 2003 survived to allow such tracking. This bird was marked in 2003 at SCR; it staged that spring on Lake Erie marshes of northern Ohio and spent most of summer in North Dakota, before moving to Hudson Bay in late summer where it remained until October. By November this bird moved to Lake Erie marshes before returning to SCR mid-December where it over-wintered. The transmitter battery expired when this duck was migrating through Ohio in spring 2004.
South Carolina Mallards
Evolving technology of satellite telemetry and project success with Northern pintails provided opportunity to track other species. Mallards were chosen due to historical importance and recent decline of wintering populations of this species in SC. A total of 6 refurbished Canada goose transmitters weighing 30 grams were made available by Cornell University. Mallards are larger than Northern pintails enabling a heavier transmitter
DNR personnel captured 6 hen mallards at 3 sites in cooperation with Federal personnel and private landowners. Two birds each were captured, instrumented and released at Santee-Delta WMA, Santee National Wildlife Refuge and Two Rivers Farms. By mid-March all mallards were migrating north. One bird moved through North Carolina before ending up in southern Michigan by mid-April. Two birds migrated straight to the Lake Erie region. The other 3 birds staged in Maryland and Virginia before moving north into New York and Ontario.
Accurate interpretation of satellite data can be difficult. If no movement occurs over a period of time, the bird has either died and its transmitter is still in a position to transmit, it shed its transmitter, or it is still alive but making only small movements within the error range of the accurate satellite-telemetry. Five of the 6 mallards marked in 2004 showed no movement during summer 2004. Signals were sporadic by fall indicating weak batteries. The last known locations for 5 mallards were northern Minnesota, southern Michigan, western New York, northern New York, and southwestern Ontario. The remaining mallard moved into the Boreal Forest of northwestern Ontario by summer but was last located off of Georgian Bay near Sudbury, Ontario in mid-October 2004.
Summary and 2005 Field Season
DNR personnel successfully instrumented 8 hen Northern pintails and 6 hen mallards with satellite-telemetry transmitters during February 2004. The 2004 Northern pintail data was similar to results from birds marked in 2003. The ducks began leaving the state in March, some on a northwestern route through the Great Lakes and others on a more northerly path through eastern Ontario and western Quebec. With the exception of 1 pintail that went to Labrador, the remainder spent most or all of the spring and summer on the coast of Hudson Bay. Fall migration began in October, as the birds headed back through spring staging areas.
Mallard satellite-telemetry data provided further insight into mallard population with an affinity to winter in SC. All 6 ducks were affiliated with the Great Lakes region or points farther west in concert with band return interpretation. This has important management ramifications to formulation of annual waterfowl hunting regulations. Additional satellite-telemetry data along with increased banding of SC wintering mallards will increase the understanding of this species and its relationship to wintering in SC.
The third and final year of the project was scheduled for 2005, but mild late winter weather was not conducive to trapping resulting in the inability to capture any Northern pintails or mallards. Pledged funding will permit monitoring of 10 satellite transmitters, and plans are to instrument both hen pintails and mallards in February 2006 to complete the final year of the project.
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