Posts Tagged ‘weather’

Where Your Purple Martins Went

Sunday, June 20th, 2010

As the purple martin season for 2010 winds down in the Southern states and hope for wannabe landlord dwindles, I have heard some folks wondering where their purple martins went. Some established colonies have even reported the complete failure of their colonies to arrive at all. In this article by Cynthia Porter from the Winona Post she describes some landlords experience with colony loss. There was some speculation about “where the martins have gone” and I hope to add some clarity to that issue.

The article mentions specifically that the martins were, “stalled in April due to low pressure systems in the south. That delay seems to have upset normal migration patterns in which birds like purple martins send scout males first, followed later by females.”

I thought that I just had to clarify this statement that seems to speak to the age old (and false) myth that purple martins will send out “scouts” ahead of the rest of the colony. Purple martins experience a staggered molt in South America and  older birds will complete molting before younger birds do. The phenomenon known as “scouts” is actually just older more experienced birds rushing “home” to secure nesting prime nesting spots. Now that we have that straightened out…

As far as why YOUR purple martins never arrived; there is only really one reason.

The colony experienced losses of adult birds, nestlings and fledglings due to predation, weather extremes (cold or drought) greater than the rate of reproduction.

Here is how that can happen:

1. Prolonged Cold Spring Snaps

2.Extended Dry Weather / Drought

3. Predation

Let me go into detail on these:

In cold weather (temps of 40 degrees F or below) aerial insects are not available and starvation will occur within days. Record Low temps for record breaking extended periods of time, made foraging for food impossible for many purple martins. So birds that may have arrived early, didn’t survive this year. Purple Martin landlords often report of “early arrivers” braving intense spring cold snaps for days and even with poor weather forecast, martins will often times continue their journey Northward and remain at their colony site. Many landlords last year and this year reported huge losses of ASY (adult) purple martins from cold snaps such as these.

Droughts were widespread and severe in many areas in 2008 even more so in 2009. Reduced rain results in reduced amounts of aerial insects thus reducing available food supply. Large losses were reported last year of thousands of dead nestlings that starved to death. According to Louise Chambers of the Purple Martin Conservation Association, “.We don’t know if adults will return after total nesting failure” so even though “many landlords are reporting a very good season this year” it could be that those adults returned or their sites attracted new adults.

The most important factor and the one WE CAN DO SOMETHING ABOUT, is predation. Most predation goes undiscovered. Without safety precautions, such as predator guards in place, raccoons and snakes can easily climb ANY martin pole and go from martin nest to martin house for an easy meal. A colony can be decimated within days. Once a gang of raccoons finds the tasty treats (your birds) at the top of your purple martin pole, it will climb every pole in the neighborhood. And believe me, I have seen it Raccoons DO eat birds! Last year at our local roost, I witnessed raccoons dining at their leisure on so many purple martins that their body parts littered the ground like confetti. You can read the post here: Davie Fla Roost.

One of the reasons why the Purple Martin Conservation Association recommends nest checks is to discover problems early. By discovering problems such as nest predation, you can monitor the health and growth of your colony. Many landlords that report complete colony abandonment have in fact been suffering chronic losses and/or predation. The ultimate failure of many colonies could have been avoided by careful observation and having predator protection installed.

So to conclude, if you don’t observe your martins and perform nest checks, your colony may have suffered losses of adults from cold weather, losses of nestlings due to dry weather and, if unprotected, losses from ground predators as well. Then that is why you had no martins return at all.

If you are interested in reading more about raccoons and the threat they pose, try this article titled, “Raccoons in our Midst”.

If you want to know what other threats there are to your colony check out this surprisingly long list, “Threats.”

©2010 PurpleMartinArt.com / S.Halpin

Nest Check for 4/5/09

Monday, April 6th, 2009

In my last post I had told you of how I finally was able to do a nest check on 1 of my 3 housing units. All because of a stubborn pole-or feeding platform to be specific. Well here are the nest check results as of April 5th.

Gourd #2- 5 eggs
Gourd #3- 5 eggs
Gourd #6- 6 eggs
Gourd #7- 4 eggs
Gourd #9 -5 eggs
Gourd #10- 6 eggs
Gourd #11- 4 eggs
Gourd #12- 4 eggs

Excluder gourd -4 eggs

Natural horizontal gourd - 3 eggs

Sunset Inn compartment A -(?) eggs-mom in nest & did not move.
For a grand total of at LEAST 46 eggs in 10 gourds and 1 nest in house. 

Next nest check is 4/7/09, I hope.

Now today was a challenging day. I had a tooth taken out and am miserable. When we came home I wanted nothing more than to curl up under the blankets and go to sleep but the weather had other ideas. We have a cold (yes COLD) front moving through and the wind is gusting upwards of 25 mph. I am confidant that my 2 Economy Gourd racks can handle this but the triangular telescopic pole…not so much. I went out with ice pack held firmly against my jaw and assessed the situation. The gusts were making the house appear to twist from side to side. Though I am no structural engineer, I am smart enough to know that this is a recipe for pole failure. I lowered the pole so that only 1 part of the 4 sections is extended. The house looks ridiculously low to the ground but the birds wont mind. My incubating female in house compartment A flew right back in without so much as a pause. My trooper. Some of the other birds hovered, then landed on one of the gourd racks before finally going back into the house. Tomorrow is a nest check day and I will raise it back up then as long as the wind is a bit more behaved.

Perhaps when I am more up to it I will tell you of the dental experience that brings me to the point of having my tooth extracted. But I must admit, talking about my birds is good therapy and I thank you all for listening!

 (c) Blog contents copyright 2009 S.Halpin/PurpleMartinArt.com

South Florida Cool Snap (Jan 16, 2009)

Friday, January 16th, 2009

The early arrival of 3 Purple Martins had me thinking that this season was ready to get underway. The cool weather and quiet attitude of my 3(?) Martins has me now thinking otherwise.

I even began to doubt if the birds were here or not. Had they only been staying a night or two to gather strength before continuing on? I would look up constantly without catching sight of any Purple Martins anywhere. So last night I sat outside and waited and waited and waited. Finally, so high that the martins appeared as specks, I saw 2 of them. Eating feverishly in the last moments of daylight. Pickings must be slim with the combination of cool weather and winds which are getting stronger today. When they could wait no longer they dove into what will be gourd #5. The male only pausing at the entrance long enough to allow his mate entrance. A brief and quiet call and he shuffled in. So, that’s the story. Early arrivers face challenges no matter the latitude. The task of foraging is keeping them busy all day and the weather is supposed to get even cooler and more windy. I doubt I will see much of the martins while the cool snap is hanging around.

 I stood there and stared at the gourd rack. I noticed something else. The third female peeking out of what will be gourd #3. Sneeky, sneeky, sneeky!

The winds are from the North now at about 10mph, gusting to 15. Showers are expected. It will be Cold all weekend. I know, I know…South Florida. We don’t know what cold is!

I will put out dried mealworms and crickets in the feeder. Supplemental feeding is not common in Florida. So the chances of them actually eating them are slim. But I will put them out and my conscience will be clean and clear.

The webcam is working great and I am waiting on another camera to hook up what will be a nest cam. I am VERY pleased with the clarity of the picture so far. It a Lorex product and the tech support is very fast and efficient. I highly recommend the camera.

Blog & Photos Copyrighted 2009: S.Halpin/ PurpleMartins-R-Us.com