The TFT website has an update on the Iowa research project. You can go read it there but a few highlights:
OVERALL, FOR 2022:
● A total of 73 hens were marked last winter.
● As of early August, 27 hens have died for a mortality rate of 38%.
● Of 63 hens available to nest starting on May 1, only 7 nests hatched successfully (i.e., hatched at least one egg; 11% hen success rate).
● Of 33 hens marked with GPS transmitters, 7 hens did not incubate a nest, 17 incubated 1 nest, 8 incubated 2 nests, and 1 incubated 3 nests.
● Most of the nest failure was due to predation, however, one nest failed due to hay mowing and one failed due to abandonment by the hen
● The median day of nest failure was 8 days, and a preliminary nest survival model indicates 50% of nests failed by day 10 of incubation.
● Of the 7 nests that successfully hatched, the average clutch size was 9.9 eggs per nest and the average number of eggs hatched was 7.7 eggs per nest.
● Of the 54 eggs that hatched, 18 poults were observed during poult captures conducted within 1-3 days post-hatch and a total of 12 poults were marked with VHF/radio transmitters. During 4-week flush counts for 6 of the 7 hens that hatched a nest, a total of 4 poults remained alive. One hen was not flushed because her transmitter failed prior to the 4-week flush count.
Lots of concerning facts, but one stands out, if I'm reading it correctly. 26 of 33 hens attempted a nest. Of those nests, 17 of the 19 nests that failed, (89%) were due to predation.
OVERALL, FOR 2022:
● A total of 73 hens were marked last winter.
● As of early August, 27 hens have died for a mortality rate of 38%.
● Of 63 hens available to nest starting on May 1, only 7 nests hatched successfully (i.e., hatched at least one egg; 11% hen success rate).
● Of 33 hens marked with GPS transmitters, 7 hens did not incubate a nest, 17 incubated 1 nest, 8 incubated 2 nests, and 1 incubated 3 nests.
● Most of the nest failure was due to predation, however, one nest failed due to hay mowing and one failed due to abandonment by the hen
● The median day of nest failure was 8 days, and a preliminary nest survival model indicates 50% of nests failed by day 10 of incubation.
● Of the 7 nests that successfully hatched, the average clutch size was 9.9 eggs per nest and the average number of eggs hatched was 7.7 eggs per nest.
● Of the 54 eggs that hatched, 18 poults were observed during poult captures conducted within 1-3 days post-hatch and a total of 12 poults were marked with VHF/radio transmitters. During 4-week flush counts for 6 of the 7 hens that hatched a nest, a total of 4 poults remained alive. One hen was not flushed because her transmitter failed prior to the 4-week flush count.
Lots of concerning facts, but one stands out, if I'm reading it correctly. 26 of 33 hens attempted a nest. Of those nests, 17 of the 19 nests that failed, (89%) were due to predation.
