Posts Tagged ‘raccoons’

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

Sad News

Wednesday, June 17th, 2009

As you know, on Saturday I dropped off a HY purple martin that I found at the Davie Roost. The apparent trauma of a tree collision (?) the martin was unable to fly and seemed to be slightly uncoordinated. I brought him to the Folke Peterson Wildlife Center where he was given some medications and observed. Today I received bad news. Apparently after he failed a flight test, he had an X-ray taken and it was found that he has a crushed shoulder. Unable to be fixed surgically, he is doomed; and though calm and comfortable, his days are numbered. I am upset at the news and so looked forward to releasing him back at the roost to join his comrades. I am so sad to think that he will meet the same fate as those that were littering the floor. Another fallen martin, another statistical failure and another purple martin that will never fly across the Equator. I will tell you when his hour comes.

The colony remains busy in the morning but quiet as evening approaches and I am looking forward to going to the roost again. I have been unable to locate any raccoon repellent at the local Lowes, hardware store, feed store, Dicks sporting goods or Bass pro shop. The ideas I have received include moth balls, metal flashing, Vicks vapor rub, large cat (like lions and tiger) feces, traps and chaining a large dog to a tree under the colony. Unfortunately, I have been unable to come through on many of those ideas. The folks at one animal removal service told me that since the raccoons have discovered the richness of the roost, that a chemical/scent repellant will be useless.