Second Clutch Possibilities ?

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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

I posted earlier on the Forum about what I thought was a re-nest. A pair that fledged 4 in mid-July, ending up with 3 more, the last of which fledged just yesterday, Aug. 24th. I figured that something must have happened to the first nest, but the more I think about it, the more I think they may have raised a totally new clutch. I understand that this is pretty rare, but possible. Considering the dates it would have been a pretty tight time line but not impossible.

I seem to get confused by at least one nest every year.

Any thoughts on this out there?

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
Ed Svetich-WI
Posts: 798
Joined: Tue Jan 13, 2004 10:05 pm
Location: Brooks, Wi (McGinnis Lake)
Martin Colony History: 24 Super and Excluder Gourds on two gourd racks, all SREH. Full occupancy. My philosophy is to maximize fledge % with existing cavities rather than adding gourds to grow colony, thus providing opportunities for new colony expansion. Fledge over 100 nestlings yearly from 24 gourds. Band nestlings in cooperation with state university. 2019 Adendum: Reduced colony size to 12 gourds to focus on more intensive management regimen.

Bill,

I documented one such occurence in 2017, as you may have read in the earlier Forum post. I nest check religiously. Plenty of nest checks and nest replacements made it possible to verify that two full nesting cycles occurred. From the first egg in the first nest to the fledging of the young on the second nesting, that particular ASY pair's season lasted 102 days. This pair was the first to produce eggs, so they had a bit of a head start which may have given them a bit longer to accomplish this feat.

I think that it is more common in the Southern part of the country where the weather stays warm longer. Maybe someone down there can add to these double clutches.

Good luck in 2021.

Ed
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

Ed;

I did read your post on the possibility of this happening. At this point I really believe that was the case with my pair.

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
lynnh
Posts: 390
Joined: Thu Jun 28, 2007 7:07 am
Location: Iowa, New Sharon

Hanover Bill, I believe I had a pair produce a second clutch in 2015. First clutch fledged 6/16/15 second clutch fledged 8/18/15.
2007 2 pair 8 fledged
2008 4 pair 18 fledged
2009 21 pair 87 fledged
2010 44 pair 174 fledged
2011 68 pair 244 fledged
2012 82 pair 364 fledged
2013 82 pair 359 fledged
2014 86 pair 415 fledged
2015 101 pair 427 fledged
John Barrow
Posts: 944
Joined: Tue Nov 11, 2003 4:12 pm
Location: Corpus Christi / Sandia , Texas

Bill,

I have authored or co-authored with Texas landlord Tony Frederickson several articles for PMCA's Update magazine pertaining to second broods. Our first article was published in 2006 and followed by my article in 2009, after identifying 3 banded males involved in raising two broods with females I believe to be the same based on careful observation during the season, timing and post fledge behavior, and simple logic. Those articles address in detail the unique timing of second broods as well as the behavior of parent birds that leads in to a second brood. I authored an article after my 2012 season in Sandia, TX, where I hosted a fairly new colony of 25 pairs and and two broods raised by 13 of the pairs. In 2015, I documented second broods at both my Corpus Christi and Sandia colonies; documenting four more banded participants, including three banded females. (A fourth banded female was observed on camera in an earlier year, that incidentally was involved as a geolocator recipient).

I cannot say whether your brood is what I would identify as a second brood. I can state that identifying a second brood requires close observation, regular and consistent nest checks and good written records, and has a unique timing (the second brood generally starting about the time the majority of SY nests are fledging). In the overwhelming majority of seasons with second broods there were more than one pair involved as a result of closely aligned pairs mimicking the other. Only twice did a single pair raise two broods in the same season--and perhaps its significant that it was in two consecutive seasons from the same gourd (neither bird of the pair was banded to conclusively identify it as the same one each year). All birds involved in second brood production have been ASY birds, and I am doubtful that an SY bird would be involved in raising a second brood.

In 2013, a 4th banded female involved in two broods was closely observed in both broods nesting in a gourd that was equipped with an in-cavity camera. She was in the act of incubating broods early in her second nesting even as some of the fledglings from the first brood were returning in the evening and stayed overnight for a couple of days, until the male blocked them out. Sadly, she incubated for a total of 21 days eggs that were infertile and did not hatch. At that point she left ending our season.

To date I have observed 40 or more second broods from my South Texas colonies. I am certain that I am not the only landlord in North America that has hosted second broods, although there have been a few folks who have questioned my observations every time I have written about them. Obviously, I landlord in an area far to the south of you, which may, or may not, be a factor of successful second broods. If you message me your email address I will be happy to share copies of articles I have authored that include behaviors that have been observed in second broods, as well as graphs for many of those showing their timing. It's really an individual's call to report a second brood. If you can justify your observations with the timing and behavioral observations to report a second brood, I am certainly happy for you.
~~TEAMED WITH A MARTIN GODDESS~~

Member/Mentor-PMCA. I do regular nestchecks and participate in PROJECT MARTINWATCH!! Coordinated 3 geolocator studies-2009, 2010 & 2013. State and Fed licensed bander (retired Jan., 2020)
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