July is usually a good time to collect alligator eggs. But that’s only true when there’s a normal rainfall in late February that continues without flooding.
This year we were very dry in the early part of the year and a rather sparse alligator mating season left us with 70 percent fewer eggs gathered this year.
In a normal year, the females begin nesting early to mid-June when they will build-up a nest and lay their eggs. Nests are built into a round, mound-type structure at night and are built from natural vegetation, e.g., broomsedge, bullwhip, cutgrass, wiregrass, available annuals and soil.
Courtship and breeding occur between April and July, depending on temperature/weather conditions in deep water.
A female may start several nests before a single nest is successfully completed. Eggs are deposited at the top of the mound and then sink to the center forming layers with vegetation. Finally, the eggs are covered with approximately one foot of vegetation. All nesting activity usually occurs within a two week period.
Nesting rates for adult females in the wild average around 60 to 70 percent where habitat and environmental conditions are excellent. That means three feet or more water for mating and no flooding.
The method and timing of egg collection is very important. Alligator embryos are very sensitive to handling (mechanical injury) from 7 to 28 days after they are laid. Many embryos will die if handled during this period.
Most alligator eggs cannot be turned or repositioned when taken from the nest (unlike bird eggs). Eggs should be marked with an “X” across the top before removing them from the nest so that they can be maintained during transport and incubation in the same position as they were laid.
Eggs that are laid upright in the nest (long axis perpendicular to the ground) will die unless repositioned correctly (long axis parallel or lying on its side and not on end) before artificial incubation. This repositioning can only take place in the first few hours after nesting.
The best hatching rates for eggs left in the wild are less than 70 percent. Hatching rates for eggs taken from the wild and incubated artificially average 90 percent or higher.
Clutch size varies with age and condition of the female. Large and older females generally lay more eggs. Clutch size should average 35 to 40 eggs (range 2 to 58).
Egg fertility can vary from 70 to 95 percent. Embryo survival can also vary from 70 to 95 percent. Hatching rate varies from 50 to 90 percent. Egg fertility, embryo survival, and hatching rate of eggs taken from the wild and incubated artificially are 95, 95, and 90 percent, respectively.
With nature out of balance, who knows what will avail itself as a problem.
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