Egg Size ??

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Hanover Bill
Posts: 615
Joined: Thu May 14, 2009 3:10 pm
Location: Pennsylvania/Hanover Township
Martin Colony History: 2009 & 10 - 0
2011 & 12 - Visitors
2013 - 2 pr. fledged 9
2014 - 3 pr. fledged 13
2015 - 7 pr. fledged 27
2016 - 15 pr. fledged 72

Is there any correlation between egg size and age of the female? I notice, what I would call, a lot of smaller than usual eggs this year. I know I have more SY Martins nesting than usual, due to early spring losses of my older birds. Would this explain the smaller eggs?

Thanks;
Hanover Bill.
2009 & 10 - 0
2011 & 12 - Visitors
2013 - 2 pr. fledged 9
2014 - 3 pr. fledged 13
2015 - 7 pr. fledged 27
2016 - 15 pr. fledged 72
ToyinPA
Posts: 2126
Joined: Mon Apr 10, 2006 6:07 pm
Location: PA/Avis
Martin Colony History: The 1972 St. Agnes flood wiped out all the Martins in my area. One day, in 1997-98, 5 or 6 Martins landed on the power wires crossing my back yard. I had no house for them. They kept coming back day after day. We got a martin house a few weeks later & they have been coming back every year since. I average 12-15 pair per year.

Not necessarily Bill. I've had ASY & SY females both lay huge eggs & tiny eggs half the size of a normal egg. Could be the weather has played a role in smaller than normal eggs this year. Are you offering crushed egg shells or oyster shells?

Toy in PA
PMCA Member
Hanover Bill
Posts: 615
Joined: Thu May 14, 2009 3:10 pm
Location: Pennsylvania/Hanover Township
Martin Colony History: 2009 & 10 - 0
2011 & 12 - Visitors
2013 - 2 pr. fledged 9
2014 - 3 pr. fledged 13
2015 - 7 pr. fledged 27
2016 - 15 pr. fledged 72

Hi Toy;

Yes, I am offering both egg shells and crushed oyster shells. They are liberal with the word "crushed", as they are pretty big pellets. I am trying to crush them into smaller pieces before feeding, but they are very hard.

Hope things are going well at your site.

Hanover Bill.
2009 & 10 - 0
2011 & 12 - Visitors
2013 - 2 pr. fledged 9
2014 - 3 pr. fledged 13
2015 - 7 pr. fledged 27
2016 - 15 pr. fledged 72
Louise Chambers
Site Admin
Posts: 6208
Joined: Tue Nov 04, 2003 1:07 pm
Location: Corpus Christi, TX

I recall a PMCA study where eggs were measured, I think we measured every egg laid that season at PMCA housing in Edinboro, PA. I know there was a range of sizes, but differences were slight, and no significant size difference was found between ASY and SY eggs.
Spiderman
Posts: 778
Joined: Thu Jan 31, 2008 9:19 am
Location: Gladewater, Texas

I live down south and our Martins feed for a long time before they start nesting and laying eggs.

I've never really noticed any difference in egg size.
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
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