<div dir="ltr">Hi Nathaniel and Tweeters,<div><br></div><div>This intersex Mallard is a really neat bird. There are a handful of reports of one at Carkeek over the last two months, which I assume is the same individual. I have photos from January 8 that I haven't yet added to eBird, that look very similar to those posted by Thomas Gergen. And Sarah Peden's photos here also look like the same bird: <a href="https://ebird.org/checklist/S129040845">https://ebird.org/checklist/S129040845</a>.</div><div><br></div><div>I did some reading on such birds when I saw this one earlier this winter. The prevailing theory is that this is typically caused by female birds losing the function of their single ovary, and thus losing production of female sex hormones. When this happens, the other gonad often develops and starts producing male sex hormones, which cause the bird to develop male traits. It's been studied most extensively in chickens. If you want to learn more about this, I'd recommend this review: <a href="https://www.karger.com/Article/FullText/448365">https://www.karger.com/Article/FullText/448365</a>.</div><div><br></div><div>Good birding,<br>Matt Dufort</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Sat, Mar 4, 2023 at 8:51 PM Nathaniel Peters <<a href="mailto:ncpeters@uw.edu" target="_blank">ncpeters@uw.edu</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div>Howdy Tweets!<div dir="auto"><br></div><div dir="auto">The monthly Carkeek Park Neighborhood Bird Outing that I lead for Seattle Audubon had fantastic luck today in the chilly wet weather, when we pretty much had the park to ourselves.</div><div dir="auto"><br></div><div dir="auto">One of the big highlights of the trip was discovering what I believe to be a gynandromorph/intersex Mallard in the wetlands around 10:15AM. We were on the boardwalk looking at the 40-50 Mallards there, when I noticed a very unusual individual. This Mallard had the crown, breast, wings, and curl feathers of a male Mallard with the cheeks, flanks, and tail of a female Mallard. The bill was very dark at the base and had a yellow/orange tip. I received confirmation from Dennis Paulson that this bird looks good for a gynandromorph, and I am fairly confident on my call. I also welcome the thoughts of others if anyone else is able to locate the bird.</div><div dir="auto"><br></div><div dir="auto">I have some decent quality iPhone pictures and am in the process of collecting more from my walk participants. I went back at around 330pm but all the ducks were gone at that time. I will probably try again tomorrow morning and see if I can relocate the bird. If anyone would me to send them the pictures, let me know.</div><div dir="auto"><br></div><div dir="auto">Happy birding!</div><div dir="auto"><br></div><div dir="auto">Nathaniel Peters</div><div dir="auto">Seattle, WA</div>
</div>-- <br><div dir="ltr"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><span style="color:rgb(0,0,0)">-</span><br></div><div dir="ltr"><span style="color:rgb(0,0,0)">May the</span><b style="color:rgb(0,0,0)"> F</b><font color="#cc0000">l</font><font color="#e69138">u</font><b style="color:rgb(0,0,0)">OR</b><font color="#f1c232">e</font><font color="#38761d">s</font><font color="#3d85c6">c</font><font color="#073763">e</font><font color="#674ea7">n</font><b style="color:rgb(0,0,0)">CE</b><font color="#000000"> be with you!</font></div><div dir="ltr">-</div><div dir="ltr">Nathaniel Peters Ph.D.<br></div><div>W. M. Keck Microscopy Center Manager</div><div dir="ltr"><div>University of Washington<br></div><div><a href="mailto:ncpeters@uw.edu" target="_blank">ncpeters@uw.edu</a><br></div><div><br></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div>
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