Question on 6x6 versus 12x12 compartments

[aarosport]

As some of you know I recently purchased the Grandpa trio house. My question is on compartment size. I had 6 mating pair last year and if I convert the house to 6-12x12 compartments does that limit how many Pairs I can have? Should I leave some in the 6x6 size? All have SREH doors on them, which will also be new to my birds. All input is greatly appreciated!

[DebA]

My second year I bought S&K's same size house, but I did convert to six larger compartments. Third year I added a second house, same thing. I suspect looking at your numbers vs mine...your growth was quicker, this could have affected my total, although I didn't fill both houses last year.

However, seeing how the babies grow and take up the nest bowl compartment I cannot image mom and dad having any space at all in a 6x6. Maybe if affects overall nestling numbers and fledgling numbers. Idk. There are so many positives in the larger compartment I cannot imagine not expanding. Space, separate space for nestlings in nest bowl which is better predator protection (further reach in) makes sense to me.

If you wish to expand your numbers, and I know this is not an easy solution, but if at all possible offer more housing in the larger compartments or gourds. Just my opinion. Good luck!

Oh and still, having 12 6x6 is way much better than no housing at all!

Deb

[DebA]

p.s.

Looking at your fledging numbers, you kicked my rear there too! I forgot to mention that my birds had no issues with converting to SREH. Well, there was one big guy last year that had trouble entering. It took him awhile to get his rhythm.
Deb

[John Miller]

this is a topic I've mulled over, and continue to do so. will offer some considerations.

Deeper compartments protect the babies better from possible predation from owls, blowing rain and maybe from siblings pushing one another out. You go from quantity housing units to quality.

But..these houses with 6 by 6 units have served martins well. Starlings generally don't try to nest in the small units -- and in situations where people put up housing and don't manage it closely (not you and me of course) and a few sparrows nest there, I wonder if it's better to have 12 units in a house than six. Not sure, but wonder about it.

One way to improve the house as-is is to use porch dividers. This separates the close units so that if an older baby gets pushed to the porch, it can't wander and get lost and maybe can sit there on the enclosed porch long enough to get back in. I'd also consider owl guards.

it's also not advised to use the SREH on 6 x 6 units because nest material may get pushed up against the small entrance and obstruct it. Some people do it and it may be okay if you watch closely for problems.

If it were me, I'd go to deeper units and hang a couple of gourds below...you'd be up to 8 units then of quality housing.

John Miller

[Craig Dyer]

My first house was a Grandpa Trio. I originally converted eight of the 6"x6" into four 6"x12". I left four as 6"x6". As I recall rarely did young that had hatched in those 6"x6" compartments successfully fledge. I remember one nest in a 6"x6" (five nestlings not more than 3 to 4 days old) where all the young vanished overnight...not a trace. I have a friend however who offers two Grandpa Trios with 6"x6" compartments only. He successfully fledges many martins year after year. He used to jokingly tell me not to rat on him & tell the Forum "martin police" about his use of 6"x6"

Eventually I converted the entire house into 6 compartments 6"x12" and hung a couple of Super Gourds below. That set-up was very popular with returning martins and was usually the first to fill up each season.

[aarosport]

Thanks for the replies. The reason why I am nervous is because my previous house was 12-6x6 compartments and was very successful. I also didn't have SREH doors on that house and didn't have too much of a problem. Just worried that all the change would cause a problem.


PS. Those SREH doors look really small, it's amazing the PM's can fit in there

[Craig Dyer]

I also started out with round entrance holes in the Grandpa Trio. The starlings had a field day. I switched all of the compartments to SREHs (crescent entrances). The martins adapted with no problem at all and the starlings moved on.

[DornCounty]

I am relatively new at this but I have a strong opinion on this based upon much evidence.. especially on Trios. I helped with 35-40 trios last season.. most of them grandpas. We ran a test on 2 houses and made 4 cavities expanded to 6x12. 3 of the 4 were occupied. None of those 3 nests lost eggs or babies. All fledged 5 young each. Out of 50 other nests I monitored none raised 5 to fledging from eggs. Sparrows holed a bunch of eggs and nests were disturbed many times, with several abandoned nests. There were also some lost due to heat because of cramped quarters.

At my home site I had 6 pairs 4 which were in expanded compartments on the MSS-12(new version of the grampa). 5 of 6 fledged all the eggs they laid. No loses due to pecked eggs and one young that died from heat.

I will know more after this season, but at least one season it seems pretty hard to dispute.

6x6 are fine, but the trio factory does NOT recommend using SREH entry holes unless you go to expanded. A theory that is backed up on here for the most part.

There were also some studies done that suggest it's tough to get more than 60% occupancy on a 12 room trio. But I have heard of it, but haven't seen it.

If you have the ability expand the compartments.. you won't regret it.

[Martin man RI]

The numbers say its all. From 1996 to 2005 five trio units all 6x6 units
NEVER more then 10 pairs. Rare sets of Six eggs, most no more then five eggs. Many females stopped in and kept flying north. The colony was
weak because of small units in 2005 storm came in and lasted five days
killed all the martins at this site.
fast forward 2006- present manage five super colony's all trio units 6x6x12 many full. large sets of eggs gourds added too. managed 90
pairs of martins total (2012) Biggest mistake in my management of martins
was having them in small units. To date most if not all martins in RI and
CT are nesting in gourds and large trio units. We have a limited number
of martins and there so smart they now avoid small trio units for the larger gourds yards with small trio units sit empty and the birds have moved to prime locations along the water front where they can nest in prime units
and habitat. All my sites are SREH and I have one site with small aluminum
unit and the birds will not use it! I have removed more small unit martin
units than anyone in New England. NO its not a good idea to have 6x6 units. My birds now produce numerous sets of six eggs and seven eggs.
Something i never had in the 1990's the females love the deep cavity.
The technology in the 1990's was the 6x6 units lets all fast forward give the birds safer units and let them produced record numbers of off spring
that way your colony will never be lost like my first one. Back in 1996
there were no gourd colony's Today its a different story. And the martins have doubled there population in CT and RI and South Eastern
MA. Because of gourds and Large aluminum Houses. Please remove or
double size your aluminum houses. There holding back the species.
-----Ray

[John Miller]

well...think you should listen to Dorn County and Martin Man. I grew up with these six by six units and it's hard for old dogs to entirely abandon their ways. Dorn County and Martin Man are still wet behind the years -- comparatively -- and have numbers to support converting to deep compartments.

John M

[Emil Pampell-Tx]

I have gotten into some heated arguments about the necessity of having deep compartments, I don't want that again, but in my opinion, all compartments need to be at least 12in deep, no matter if its a Trio or something else. Why not do it, and switch to SREH, they do work great.

[aarosport]

Thanks for the info. I took my mss-12 house and converted it to the larger sizes with SREH. Just curious, do most pairs have their nests in the back 6x6 compartment in the enlarged compartment?

[Craig Dyer]

Every female martin that has ever built a nest in the modified Grandpa Trio that I offer has built it in the compartment furthest from the entrance hole. I believe this is instinctive behavior.

[Louise Chambers]

Many thanks to our new board member, Larry Melcher, who is doing an awesome job! This video helps explain the hows & whys of larger rooms for martins.

https://www.youtube.com/watch?v=p_UjRsBmoMQ

[Thurman Seber~TN]

Belive me, I have been through this before. Many years ago on the first colony I had I used all 6x6 compartments. Much later when I decided to start another colony I tried both sizes to decide which worked best for me. Without any doubt whatsover, the martins chose the larger compartments and used them up before any would nest in a smaller compartment.. Yes, it is very possible to have a colony using small compartments.. But try some both ways and just see which way they choose. I think I know what I am talking about but you will be better satisfied to test it yourself