Archive for June, 2010

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

Purple Martin Season Is Over for 2010

Thursday, June 17th, 2010

SY maleIt’s official, the last of the nests have fledged and all the babies have taken to the air. A hawk was making daily visits and though I am sure (s)he got at least 2 fledglings, I am sure more fell victim. I was unable to get a good look so I am hoping it was the resident Red Shouldered Hawk, a slower and larger hawk that poses a formidable threat but less so than the smaller faster Coopers Hawk that are common in South Florida also.

The Red Shouldered hawks nest close by and protect this as their territory from other hawks. If that can be counted as protection…I am not too sure.

Night time is quiet and I am not sure if many martins are returning to the nests to roost at night. They may have moved on to a local assembly area or pre-migratory roost. The fact that I am talking about the roosts already almost sounds crazy! Can time have flown by so fast? I guess I will start planning another trip to the roost in Davie this year.  It has almost been exactly a year since I went to see it and video taped it. You can see it at my blog post titled Purple Martin Pre-Migratory Roost Spectacular. It is a great YouTube clip taken at the roost with swarms of purple martins.

The webcam will not be up again for the remainder of this year as the computer I had it running on is dead. I plan on replacing it as soon as I can and it will be up again next January. I promise.

©2010 PurpleMartinArt.com / S.Halpin

Afternoon Storms and Brutal Heat

Wednesday, June 9th, 2010

With the heat index in the 100′s the fierce thunderstorms are ALMOST welcome. I say almost because with each of these storms severe winds of upwards of 45 MPH that would last past sunset, have inflicted some damage.

The nest of mockingbirds right outside our garage was blown down and the 2 partially feathered nestlings had perished. The large Sabal Palms lost a few fronds and the seed pods that the mockingbirds had made their nest in was woefully inadequate for the punishing winds.

The purple martins hung on to their perches well into the night seemingly afraid to detach themselves. I suspect an attempt to find protection within their nests would have had them blown away at some point during the storm. Fortunately the storm died down and all seemed quite but the previous week had these storms coming in almost on a daily schedule.

The winds were no problem for the martin poles. So other than the mockingbird casualties, all is well. Unfortunately the same can not be said for the laptop which ran the colony cam, so no live web cam at the moment. A new laptop is on the want list…any one???