Lesser scaup (Aythya affinis) Trapping Trial in Central Alberta, 2005


Andy Murphy


I designed, built and evaluated two “bait traps”, a “loafing trap” and a “decoy trap” for lesser scaup (Aythya affinis) – hereafter scaup. A two‐man crew could easily deploy all of these traps, and a single person could deploy the loafing trap. Two additional decoy traps were constructed, but not deployed or evaluated. These latter designs were abandoned ‐ as experience with the bait traps indicated that they would not have been effective. In addition, Jim Potter, Paul Jones, and I also attempted to “drive” a scaup pair into a mist net on June 1, 2005.

The two bait traps were deployed on May 27, 2005. The bow trap and the decoy trap were deployed on June 12, 2005. All traps were monitored at least twice daily until June 22, 2005 (72 trapping days). Scaup were extremely “trap shy”. They did not use loafing platforms attached to the bait traps for almost two weeks after the traps were deployed. No scaup were captured during this trial. The only incidental capture in the constructed traps was a mallard (Anas platyrhyncos) duckling. This duckling became entrapped in a hole in the plastic snow fence, and succumbed ‐ apparently to exposure. A savannah sparrow (Passerculus sandwichensis) and a sharp‐tailed sparrow (Amodramus caudacutus) were captured during the mist‐netting attempt. They were released without injury.

While I did not capture scaup during this trial, the effort has provided observations and experience that may lead to the development of effective strategies for scaup capture. Floating rope “sweeps” were somewhat effective at diverting scaup toward traps, and a tape recording of a scaup hen seemed to attract scaup pairs. I suggest that much larger traps (constructed from bird netting) may provide an effective means of capturing scaup on the breeding grounds. One or more “hazers” (using night vision goggles) and floating rope “sweeps” may enhance the efficiency of these traps. Broadcasting a hen scaup recording may also prove to be an effective means of attracting scaup pairs to these large traps.

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