Details

Autor(en) / Beteiligte

• Ohde, Bill R.
• Bishop, Richard A.
• Dinsmore, James J.

Titel

Mallard reproduction in relation to sex ratios [Anas platyrhynchos; Iowa]

Ist Teil von

• The Journal of wildlife management, 1983, Vol.47 (1), p.118-126

Ort / Verlag

The Wildlife Society

Erscheinungsjahr

1983

Beschreibungen/Notizen

• Eighty-nine drake and 47 hen mallards (Anas platyrhynchos) were marked during a 2-year study of mallard breeding strategies in north central Iowa. An attempt to equalize the drake-predominated sex ratio by removing 117 drakes and releasing 45 hens had no apparent effect on observed sex ratios. Both drake and hen mallards were persistent in their breeding efforts and showed flexibility in remating patterns. Drakes usually remated with their original hens, but 8 (25%) of 32 drakes mated with 2 or 3 different hens during the same breeding season. Some drakes were active breeders from April to July. Hens usually remated with their original drakes, but 2 hens that had mates removed before nest destruction and 1 hen whose mate deserted her remated with previously paired drakes. Extra drake mallards were not essential for successful renesting by hens in our population. This suggests that drakes in excess of a 50:50 sex ratio could be harvested with little effect on production.