Arrival dates - causes?

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Brad Biddle
Posts: 523
Joined: Wed Feb 17, 2016 6:22 pm
Location: Marshall County AL

I hope I can explain my question, so that it makes sense. What causes the arrival times to vary from one colony to the next? It can’t be age of colony and here’s why I say that. Just up the road, a half mile from my house is a colony that’s been there for over 30 years. I know for sure it’s been there that long because I dated the guys niece in high school and he had them then. I graduated 31 years ago....

His colony has approximately 32 natural gourds. Crescent entrances. He’s pretty much full up every year. I don’t ever remember seeing Martins at his colony before early to mid March.

My colony started 17 years ago, since at least the 4th year has had arrivals back, averaging Feb 13th. I do have more gourds total but my colony is actually 2 colonies. One with 48 gourds and one with 54 gourds, so they aren’t much larger than his.

While waiting on my Martins to return this year I studied the scout report. I looked at 2 other sites that I know the landlords and while they both had arrivals this year before I did, in most years theirs didn’t return until March either.

It just seems odd that even though I typically have retuning Martins in mid February, that others around me who have been doing this as long or longer than I have, don’t get them back until early to mid March.

Thoughts?
Martin landlord since 2003. Currently offering 132 plastic gourds with tunnels and all SREH.
Rafke77
Posts: 30
Joined: Sun Jan 12, 2020 10:47 pm
Location: Plymouth, IN
Martin Colony History: 2020 first arrived 3/27. 21 pair, 92 fledged, 9 non viable.

2019 first time with Martin's, first arrived 4/24 10 pair, 24 fledged, 15 eggs non-viable.

Maybe just the paths certain groups take? It would be interesting to GPS tag several small colonies from different regions and study their flying pattern over the course of a few years, just to see if they take the same routes, and to see if their fledglings follow the same path and time for migration as their parents. Unfortunately that would be a huge undertaking and be expensive.

Something also that I'm wondering, that I just posted on another thread. Do you supplemental feed? And does your the guy with the natural gourds supplemental feed?

There is the video somewhere on this site from the Erie location where they did that. It would be interesting to see if that would have continued for a couple years if they would have taken the exact same routes.
Brad Biddle
Posts: 523
Joined: Wed Feb 17, 2016 6:22 pm
Location: Marshall County AL

I have fed but that was over a decade ago. We very rarely have a need to feed here. I would imagine that the birds that nest at the colony 1/2 mile away and mine fly the same migration path.

Early on, the year that my colony jumped from 30ish pair to 74 pair I was somewhat concerned that I had “stolen” some of his Martins. I saw him one day and asked how his Martins were doing and he said that was the best year he’d ever had.

Just more to scratch my head about.

Another thought that I’ve had, is do Martin colonies within a close proximity behave as one mega colony? Between my 2 sites at home I currently have 102 gourds. My neighbor next door had a colony with around 30 pair but lost them to gourds falling apart and starlings taking over. And the guy up the road has around 32 pair. I can see all 4 sites from my back yard. I have 2 racks down at the barn that will be nearly full before I have many birds in my back yard. I’d have birds in my back yard before my neighbor did and so on.

I’m wondering if the “neighborhood” Martins just see all 4 sites as home and the first ones to return pick their favorite cavities from among all 4 sites?

Fortunately I asked my neighbor last year if I could come over and kill Starling’s off his gourd racks. He told me that I could, so I did. He then told me he wanted to get new gourds, just like mine for this season. So he’s got 32 troyers to hang now as soon as he picks them up from my house. I’m hanging 60 more gourds this year too, but I’d bet he gets Martins back at his place this year too. At least a few pair. His racks are about 120 yards from mine at my house.
Martin landlord since 2003. Currently offering 132 plastic gourds with tunnels and all SREH.
deancamp
Posts: 425
Joined: Wed Mar 16, 2016 9:17 pm
Location: Raymore, MO

Could it be individuals within a clony that have the drive to come back early and that competition pushes each other. ??? These things intrigue me as well. I like to know why.
deancamp
Posts: 425
Joined: Wed Mar 16, 2016 9:17 pm
Location: Raymore, MO

We know for a fact that SY birds return significantly later. I don't even know why that is. Is it because they have not experienced the mating process to understand how difficult it can be to find a mate and successfully raise young , so they don'tfeel the push???
randyM
Posts: 101
Joined: Thu Jun 18, 2015 2:30 pm
Location: Long Lake SD
Martin Colony History: 2006 - SY pair, unsuccessful nest attempt, 3 houses = 52 cavities

2010 - ASYM + SYF pair - male disappeared after storm, female fledged all 4 young.

2015 - Lone SYM stayed month of June...added 8 gourds = 60 cavities

2016 - 1 nesting pair (ASYM + SYF) 2/3 eggs hatched 2 young fledged.

2017 - 4 nesting pairs, 16/17 eggs hatched, 16 fledged, 16 banded - 2 banded SY returned in 2018 (12.5%), added housing: 11 houses w/gourds, 4 gourd poles = 376 cavities

2018 - 10 nesting pairs, 46/52 eggs hatched, 45 fledged, 29 banded - 3 banded SY returned in 2019 (10.3%)

2019 - 32 nesting pairs, 145/160 eggs hatched, 139 fledged - 87 banded - 12 banded SY returned in 2020 (13.8%).

2020 - 35 nesting pairs, 180/199 eggs hatched, 178 fledged - 150 banded.

Perhaps you answered your own question by indicating you control starlings at your colony and the others don't. It's possible the first few ASY martins that arrive in your neighborhood stop by their home site from last year but get harassed by starlings at nearby sites and flock to your "starling-free" colony where they wait a while for a few more of their individual colony members to arrive. Once a few of last year's members from the other colonies arrive in your neighborhood they have enough members to counter attack any starlings that may have been intimidating the first few returning martins to each separate colony. There is always more safety in higher numbers. The birds from your colony likely would not be interested in going to another nearby colony to help combat starlings, as they have nothing to gain directly from fighting someone else's territorial battle. So early arriving members from other neighborhood colonies may just be using your colony (or some other "safe" location) to wait for reinforcements to show up to deal with the starlings with more force. Of course this is all just speculation, and we really won't ever completely understand why certain wildlife species or individuals behave the way they do.
Rafke77
Posts: 30
Joined: Sun Jan 12, 2020 10:47 pm
Location: Plymouth, IN
Martin Colony History: 2020 first arrived 3/27. 21 pair, 92 fledged, 9 non viable.

2019 first time with Martin's, first arrived 4/24 10 pair, 24 fledged, 15 eggs non-viable.

Brad Biddle wrote:
Tue Mar 03, 2020 10:40 am
I have fed but that was over a decade ago. We very rarely have a need to feed here. I would imagine that the birds that nest at the colony 1/2 mile away and mine fly the same migration path.
True they could be part of the same larger colony, but you know the way humans only know one way to their home and when the road home or closed everyone becomes lost, maybe the same way with the Martin's lol.

Also liked pointed out, maybe that you controlled the Starling issue, and your neighbor doesn't. Maybe the natural gourds are just not as attractive, maybe the way they're hung, hard really to tell.
Last edited by Rafke77 on Tue Mar 03, 2020 8:35 pm, edited 1 time in total.
Brad Biddle
Posts: 523
Joined: Wed Feb 17, 2016 6:22 pm
Location: Marshall County AL

deancamp wrote:
Tue Mar 03, 2020 11:11 am
Could it be individuals within a clony that have the drive to come back early and that competition pushes each other. ??? These things intrigue me as well. I like to know why.
Yes that's supposed to be the reason that the earliest ones come back early, but that drive would be common in each colony. My earliest ones arrive on average nearly a month earlier than his do. That leads me to suspect that the birds see these colonies (4 within a half mile) as one large functioning unit. I've never heard that hypothesized before, but I as of now I can't come up with another theory.
Martin landlord since 2003. Currently offering 132 plastic gourds with tunnels and all SREH.
Brad Biddle
Posts: 523
Joined: Wed Feb 17, 2016 6:22 pm
Location: Marshall County AL

deancamp wrote:
Tue Mar 03, 2020 11:31 am
We know for a fact that SY birds return significantly later. I don't even know why that is. Is it because they have not experienced the mating process to understand how difficult it can be to find a mate and successfully raise young , so they don'tfeel the push???
IIRC, I've read that the molt on HY birds takes place later than it does SY's (who become ASY's after their first molt) and ASY's. If that's so, then that's why the SY's return later. They have to wait for the regrowth of their feathers to be completed before they head back.
Martin landlord since 2003. Currently offering 132 plastic gourds with tunnels and all SREH.
Brad Biddle
Posts: 523
Joined: Wed Feb 17, 2016 6:22 pm
Location: Marshall County AL

randyM wrote:
Tue Mar 03, 2020 2:33 pm
Perhaps you answered your own question by indicating you control starlings at your colony and the others don't. It's possible the first few ASY martins that arrive in your neighborhood stop by their home site from last year but get harassed by starlings at nearby sites and flock to your "starling-free" colony where they wait a while for a few more of their individual colony members to arrive. Once a few of last year's members from the other colonies arrive in your neighborhood they have enough members to counter attack any starlings that may have been intimidating the first few returning martins to each separate colony. There is always more safety in higher numbers. The birds from your colony likely would not be interested in going to another nearby colony to help combat starlings, as they have nothing to gain directly from fighting someone else's territorial battle. So early arriving members from other neighborhood colonies may just be using your colony (or some other "safe" location) to wait for reinforcements to show up to deal with the starlings with more force. Of course this is all just speculation, and we really won't ever completely understand why certain wildlife species or individuals behave the way they do.
I wasn't clear enough. There are two neighbors. The one 1/2 mile away does control nest competitors. The one next door is the one who didn't and he ended up losing his whole colony. The one 1/2 mile away is the one with at least a 30 year old colony whose birds never come back before early to mid March. He's a good landlord and has a good colony, so it doesn't make any sense to me.
Martin landlord since 2003. Currently offering 132 plastic gourds with tunnels and all SREH.
deancamp
Posts: 425
Joined: Wed Mar 16, 2016 9:17 pm
Location: Raymore, MO

I'm not following the idea that they see the 4 colonies as one functioning unit. Are you thinking all the ones from the 4 colonies that are competing to get back first are all coming to your colony?
Brad Biddle
Posts: 523
Joined: Wed Feb 17, 2016 6:22 pm
Location: Marshall County AL

I was tossing that out there for discussion... I don't know that I believe it, but I won't say that I don't.

Yes I'm wondering if all the birds from those 3 (use to be 4) locations, come back to those 2 racks at the barn that seem to be the most popular first. I know that would go against conventional wisdom, but my site having arrivals 2-4 weeks earlier than a colony twice it's age doesn't follow conventional wisdom either. This isn't just a once or twice thing. It's every single year. That mans gourd racks are not more than 50 yards off the road, just up from a stop sign. I drive by slowly (due to the stop sign) multiple times per day. He doesn't have any back yet. I had my first one spend the night at the racks behind the house last night. I've got 20 or more at the racks behind the barn.
Martin landlord since 2003. Currently offering 132 plastic gourds with tunnels and all SREH.
deancamp
Posts: 425
Joined: Wed Mar 16, 2016 9:17 pm
Location: Raymore, MO

Yeah, can't say that it makes sense to me, but it makes me think the opposite. That all sites are working on their own "rules". I have trouble believing that they are changing sites as they push to be the first ones back. Very interesting for sure.
Archer
Posts: 757
Joined: Fri Mar 11, 2011 1:09 pm
Location: Manitoba/Altona
Martin Colony History: six pair in 2014, have grown to 52 pairs in 2017.

Fact, martins are gregarious, meaning they like to be with other martins. Maybe you have some early arrivers in your colony and everbody likes to hang out until their own gang shows up? In cold weather communal roosting requires martins to get together. Maybe you are closer to a preferred feeding site. Large bodies of water will be a source of insects when times are tough. When its cold here and there are no flying insects over the prairies, our swallow species all head to the local lagoon to skim over the water catching emerging insects.
2011- first year trying, a few visitors.
2012-One ASY pair, raised two young, lots of subby visitors. So thankfull.
2013-daily subby visits.
2014-Six SY pairs
2015-18 pair, 83 fledglings
2016-36 pair, 147 fledglings
2017-52 pairs, 192 fledglings.
2018-60 pair, 246 fledglings.
2019-59 pair, 238 fledglings.
deancamp
Posts: 425
Joined: Wed Mar 16, 2016 9:17 pm
Location: Raymore, MO

I can see them hanging out together, but I would think they would return to the colony they nest at for bedtime and to check in periodically. IMHO
Brad Biddle
Posts: 523
Joined: Wed Feb 17, 2016 6:22 pm
Location: Marshall County AL

I agree. I don’t think they’d spend the night in my gourds if they belonged at the other colony. Not trying to shoot down your ideas but I I also don’t think preferred feeding area has anything to do with it either because we’re only talking about 1/2 mile. That’s 30 seconds flight time for a lazy Martin. :grin:

At the end of the day, I think anything decided on this will be purely speculation.

I do know that I wouldn’t be the only landlord who has this situation occur.

I think that I can safely rule out colony size as a factor because there isn’t much difference between 32, 48 and 54 gourds. When I add the 60 gourds to my site behind my house this season, then that may tip the balance to the site behind my house. It also may take a year or two for it to take effect
Martin landlord since 2003. Currently offering 132 plastic gourds with tunnels and all SREH.
TravisF
Posts: 22
Joined: Sun May 26, 2019 4:37 pm
Location: Missouri

Honestly, I think you might be on to something, Brad.

My interest in purple martins started 30 years ago as a child helping my grandfather take care of his martins. He and his good friend started "landlording" probably 10 years before I was born, and they took great pride in it. They each had two homemade 24 unit houses, but his friend also had a couple racks with natural gourds. Also, their homes were about 400 yards from each other.

Sometime in my teen years, my grandpa read somewhere that martins needed larger compartments, so one winter he made four new 12 compartment houses, each with 6 X 12 rooms instead of 6 X 6 rooms. A couple years after that is when things really started to change.

Until the upgrade, both my grandfather and his friend started getting returning birds by the second or third week of March. Year after year they would both start getting birds at the same time. However, I think it was at the start of the second season after my grandpa made the upgrade that things started to change. That year, I believe he had 7 or 8 martins before his friend started getting birds. Over the next several years, it got to the point that my grandpa's "colony" would be almost completely full before his friend started getting birds.

It's funny now remembering this, because I can vividly remember my grandpa giving his friend hell, telling him he needed to get off his lazy butt and make better housing! They always referred to the martins as "our" birds, and they just casually talked about how grandpa would get the birds first because he had better housing. What really makes me think Brad might be onto something is what happened several years after the upgrade.

One year my grandpa's friend had a couple really unique martins at his colony. One had a couple completely white wing feather, and another had a couple white tail feathers. Knowing what I know now, they were SY males here for their first breeding season. The next year, like usual, my grandpa's colony started filling up before his friends, and those two male martins ended up changing locations to my grandpa's colony. If I remember correctly, one of them nested there two years, and the other three years. We know they were the same birds because of their unique coloring.

Now, keep in mind both colonies would always be full by summer time, but my grandpa's colony ALWAYS filled up first after he went to bigger compartments. They always held the view that all the martins in that area were of one big colony, and whoever had the better setup would get martins first, and once full or nearly full, they would start to spill over to the less favorable housing or less favorable areas. Yes, it's a very simplistic and non-scientific view, but it does make me wonder if there might be something to what Brad says. Maybe a martins site tenacity encompasses an area much larger than we think, maybe even an area of 1/4 mile, and that martin will nest in the most favorable compartment within that area that he or she can obtain. What I do know is that I witnessed first hand a couple male martins successfully nest as SY birds at one site, then move 400 yards to another site as ASY birds and successfully nest there for consecutive years for what appears to be no other reason that better housing.

This just makes me think that maybe you're right, Brad, and the early arrivals in your area prefer your housing for some reason, and as they continue to trickle in they spill over to the less favorable housing in that area, eventually ending up with smaller "sub colonies" within one large colony as a whole.
Brad Biddle
Posts: 523
Joined: Wed Feb 17, 2016 6:22 pm
Location: Marshall County AL

That is an awesome story. Your grandfather certainly made a lasting impression on you with his love for Martins. That's interesting that you have actually been able to see, because of those unique feathers, birds do what my theory suggests. I'd love for someone to do a banding study on this.
Martin landlord since 2003. Currently offering 132 plastic gourds with tunnels and all SREH.
deancamp
Posts: 425
Joined: Wed Mar 16, 2016 9:17 pm
Location: Raymore, MO

Travis, that is some solid information with a timeline of activity to support Brad's theory.
Brad Biddle
Posts: 523
Joined: Wed Feb 17, 2016 6:22 pm
Location: Marshall County AL

Just another anecdotal update.....

My racks at the barn are around 300 yards from my racks in my backyard. They are on the top of a ridge that runs through our community. Elevation wise, they are probably 20 feet higher than the racks at my house. I put the first rack up at the barn in 2004, the year after I put up a rack at the house we moved back here from. The next year I added another rack, 30 yards further away from the barn. In 2006 we were already making preparations to build a house here and I added one more rack at the barn, another 20 yards further from the barn than the 2nd pole and I added one pole here where the old house that we remodeled is......

There are currently 56 gourds at the barn and 48 in my back yard. Not much difference.

So, the racks in my back yard are 14 years old and the oldest rack at the barn is 16 years old. The racks at the barn, are in as good a location as any racks, anywhere, owned by anyone, that aren't on the end of a dock on a lake. They're on top of a hill, with open pasture on 3 sides. The birds can drop off the racks and gain elevation over 1/4 mile if they want to. My mom planted some ornamental magnolia tree around 50 feet from the closest rack to the barn. It is now about 20 feet tall, basically the same height as that gourd rack. It's still a great location for a gourd rack, but that tree, even 50 feet away bothers the Martins.

Even with the early Starling trouble that I had last year, I had a near full house at both sites. Age structure should be very similar between the two sites, they've been around a long time. So if conventional wisdom is correct, then I should have about the same amount of Martins at both locations, correct?

Well I don't. The two racks furthest from the barn are at least 75% occupied by at least one Martin. There are ZERO birds staying in the rack closest to the barn. (It's at least 60 feet from the barn) and in my back yard, there were 3 Martins that came to roost this evening. I still have not seen a single Martin at my neighbors house, 1/2 mile up the road. His racks are on the same ridge that the gourd racks at the barn is on. He just doesn't use as large a gourds as I do. Around 40 there, 3 here.

The more I think about this, the more I think that these Martins are seeing this 1/2 mile area as one large colony. Again I could be completely wrong, but if Martins didn't move between sites, based off absolute best location, then I feel pretty certain that I'd have as many in my back yard as I have at the barn, or at least a much closer to even amount.
Martin landlord since 2003. Currently offering 132 plastic gourds with tunnels and all SREH.
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