Date: 1/14/20 10:43 am
From: Janine Perlman <jpandjf...>
Subject: Re: Unusual Behavior Update
Thank you for the update, Ed.

Many seasonally breeding animals, including most birds, have
regressed/inactive gonads during non-breeding seasons. So I assumed the
egg-layer wouldn't even have mated. This, from the BNA American Robin
account, is interesting:

At the peak of egg-laying (first brood), males testes are fully
spermatogenic and females have enlarging follicles and/or have
ovulated at least once. In sw. British Columbia, testes reached
maximum mass throughout May; fully ripe ovarian follicles were
observed most frequently in early May. Initial declines in
testicular weight began in early June, although testes were fully
spermatogenic throughout the month. By the latter half of June,
ovulatory activity in females rapidly declined. In July, gonads of
both sexes became inactive (Kemper and Taylor 1981
<https://nam03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbirdsna.org%2FSpecies-Account%2Fbna%2Fspecies%2Famerob%2Freferences%23REF64885&amp;data=02%7C01%<7CARBIRD-L...>%7Cf612d122931649f731df08d7992173eb%7C79c742c4e61c4fa5be89a3cb566a80d1%7C0%7C0%7C637146241720802275&amp;sdata=WM8UZDcUdQUKJigndtCx909V2g4M4%2BblevbwwJDiy7g%3D&amp;reserved=0>).
However, there are several records of robins nesting in fall and
winter (Sep: Nebraska, Tennessee, Ohio, Michigan, Illinois, Alaska,
and Québec; Oct: Massachusetts and Manitoba; Nov: West Virginia;
Jan: Ohio; Gardali and White 2003
<https://nam03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbirdsna.org%2FSpecies-Account%2Fbna%2Fspecies%2Famerob%2Freferences%23REF64917&amp;data=02%7C01%<7CARBIRD-L...>%7Cf612d122931649f731df08d7992173eb%7C79c742c4e61c4fa5be89a3cb566a80d1%7C0%7C0%7C637146241720812280&amp;sdata=jaqkfxSjtBAqwHcPp2sKW0OFpmHtmgbkLaxASJre3W8%3D&amp;reserved=0>).
Although these constitute a small percentage of all nest records
examined (< 0.1%), recent research in Missouri indicates that the
majority of Oct nests were successful (8 of 10 nests fledged young;
Gardali and White 2003
<https://nam03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbirdsna.org%2FSpecies-Account%2Fbna%2Fspecies%2Famerob%2Freferences%23REF64917&amp;data=02%7C01%<7CARBIRD-L...>%7Cf612d122931649f731df08d7992173eb%7C79c742c4e61c4fa5be89a3cb566a80d1%7C0%7C0%7C637146241720812280&amp;sdata=jaqkfxSjtBAqwHcPp2sKW0OFpmHtmgbkLaxASJre3W8%3D&amp;reserved=0>).

Janine Perlman
Alexander Mt., Saline Co.

On 1/14/2020 9:22 AM, Ed Laster wrote:
> The 3 Robin eggs that were reported Jan. 8, 2020 have been abandoned and the adult has not been seen in 5 days. I don’t think it is likely that the parent could have raised any chicks this time of year, even if she had been able to hatch them.
>
> Maybe she will be back this spring.
>
> Ed Laster
> Little Rock


 
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