Question about "heat index"

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John Miller
Posts: 4773
Joined: Mon Mar 22, 2004 9:11 pm
Location: St. Louis, MO

Seeking opinions.

Are martins affected by the "heat index" or "feels like" temp?

We've just gone through a hot spell in St. Louis. To listen to TV reports, you'd think it had never been July here before. Our highest temps -- now subsided -- were 98, and a handful of remaining martin nests survived, with venting and shade. But weather reports keep saying it felt like 110 or so.

I lost babies in the very hot summer of 2012, but actual temps then were hotter, hitting 108 a few days. Yet, I think the "heat index" during that period actually was less, with low humidity.

Anyway, I watch temps closely when the martins are here, just not sure if the heat index impacts them.

John Miller
Dave Reynolds
Posts: 1919
Joined: Mon Jan 31, 2011 4:35 pm
Location: Little Hocking, Oh.
Martin Colony History: 2018 Success at my Satellite Site “Oxbow Golf Course”.
2019 Success at my home Site "Little Hocking, Ohio".

... Good question,, John... It’s just my opinion but I don’t think animals or birds feel the “feel like” temp that we feel.. It’s like the “wind chill numbers””,, I don’t think they feel that either.,, just humans.. Hopefully more will chime in on the subject...

Home Site “Little Hocking, Ohio”
2010 / 2018 -- Lots of Visitors
2019 — 1 Pair, 5 Eggs, 5 Babies, 5 fledged. :wink:
2020 — 1 Pair, 4 Eggs, 4 Babies, 4 fledged. :wink:
2021 — Waiting on March 2021

Satellite Site “Oxbow Golf Course”
2018 -- 15 Pair, 58 Eggs, 38 Hatched and 36 Fledged :wink:
2019 — 26 Pair, 128 Eggs, 99 Babies and 97 Fledged. :wink:
2020 — 30 Pair, 156 Eggs, 137 Babies and 137 Fledged. :wink:
2021 — Waiting on March 2021

PMCA Member
Posts: 132
Joined: Tue Mar 03, 2015 12:18 pm
Location: PA/Erie

since martins cool themselves by panting (which works via evaporative cooling), higher humidity levels can exacerbate the effects of extreme heat. so, yes it affects them. but, since they don't sweat, they don't feel it effects of high humidity quite like we do.
Posts: 796
Joined: Thu Jan 31, 2008 9:19 am
Location: Gladewater, Texas

From what I have experienced when the temperature gets above 100 degrees you are goin to start seeing problems. Babies jumping and other dying in their houses.
2008 - 33 PAIR - FLEDGED 96 YOUNG
2009 - 51 PAIR - FLEDGED 166 YOUNG
2010 - 45 PAIR - FLEDGED 146 YOUNG
2011 - 33 PAIR - 128 HATCHED, 97 FLEDGED
2012 - 37 PAIR - 119 HATCHED, 101 FLEDGED
John Miller
Posts: 4773
Joined: Mon Mar 22, 2004 9:11 pm
Location: St. Louis, MO

Thanks all for your insights. I have tried to blissfully disregard the heat index, and the dew point, which local meteorologists like to present. But, based on bio Joe's explanation, I should pay attention. I do think shade and venting help keep martins a little cooler. Venting probably helps most when there is a slight breeze, so I watch the tree tops and if they are moving just a little on a hot day I'm more hopeful.
John M
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