A gadwall hen with an external backpack PTT transmitter prior to release.

It used to be that a durable set of waders, a good pair of binoculars and a notepad were all the working gear a waterfowl biologist needed to study ducks. But now biologists in are spending some of their time in front of a computer screen, downloading the type of data that they could have only dreamed about just a few short years ago. Sophisticated software and hardware are giving waterfowl biologists an almost instant overview of duck behavior.

The recent advent of compact satellite transmitters that can be attached to individual ducks and geese has opened the door to many new research opportunities. This technology became available in the early 1990s, but only recently has it been miniaturized for use with small birds such as the mallard.

These small transmitters emit high-frequency signals received by satellites orbiting the earth. The satellites the relay the locations of these signals to ground-receiving stations in real time, allowing researchers to receive data from many birds at once. Without the use of satellite transmitters, researchers would not be able to trace the movements of individual birds over such an expansive geographic area.

Visitors to the DU website can track the movements of several ducks involved in three studies. This spring, a research team led by Dr. Alan Afton of Louisiana State University implanted satellite transmitters in 17 female lesser scaup captured on Poll 19 of the upper Mississippi River. The primary objective of this research (www.ducks.org/scaupstudy) is to estimate how long individual hens remain on spring staging wetlands in the upper Midwest and Canada. Biologists suspect that one of the reasons for declining scaup populations is a shortage of food on spring staging areas. They also believe many hens must spend more time on staging areas to acquire fat reserves needed for breeding. The researchers also will track where the birds breed, migrate this fall and winter.

Visitors to the DU website can also follow the movements of 25 gadwalls that are part of a satellite tracking study conducted by DU and partners in the Gulf Coast Joint Venture (www.ducks.org/gadwallstudy). Over the winter, researchers captured the gadwalls in south Louisiana and Texas and implanted them with satellite transmitters. The researchers tracked the birds throughout the wintering period, and batteries on many of the transmitters should remain active well into the summer, providing information about the birds’ migration and breeding habits.

A third DU study is tracking the seasonal movements of black ducks. Populations of these prized birds have declined by as much as 60% on traditional wintering areas. Several explanations exist for this decline, one of which is loss and degradation of quality wintering habitat. To find out more, DU is conducting research examining black duck behavior and habitat use on key staging and wintering areas in Atlantic and Mississippi flyways (www.ducks.org/blackduckstudy).

The first step in good management is a complete understanding of the issues. A strong biological foundation driven by scientific research continues to be the cornerstone of DU’s habitat work.

Check Out:

Lesser Scaup Tracker

Gadwall Tracker

Black Duck Tracker

Nesting research