Impact of drig irrigation sprinkler on super gourd temps

[lwilg]

Since all but 2 of my martins have fledged, I decided to do a small experiment to see the impact of the drip irrigation sprinkler set on the top of the pole. The very fine sprinkle was set at lowest flow rate so it fell down on the super gourds hanging 3 feet below the sprinkler. The ambient temp today is 102. I put thermometers in gourds facing the west. One was in an empty gourd with no sprinkler. The other was in a gourd under a sprinkler. The gourd under the sprinkler had an internal temperature of 93, while the gourd NOT under the sprinkler had an internal temperature of 109.
I did not have any birds jump early and of the 70 birds hatched, I did not find a single dead bird inside a gourd.
Also, none of the super gourds had wet nests from the sprinkling. I suppose water could get in, but it would take a strong wind to blow it through the cresent door. It could possibly run down the hanging wire through the holes drilled in the top of the gourd through which the hanging wire is threaded. But there was no evidence of that.
I have read about concerns with high humidity. I have not tried to check humidity inside of the gourds. High humidity at 93 degrees, if it was present, did not impact bird survival. I can not find evidence, although I may not have looked in the correct places, that high humidity in itself is dangerous to birds. I have found examples of pet places using swamp coolers inside buildings with temperatures over 105 which resulted in negative impacts on birds. It could be possible that high humidity could promote an environment in which some disease agents could grow, but again, I have not found evidence for this in my birds or searching online.
These drip sprinklers do not use much water, especially when set at lowest level. Since the poles are in my back yard, the light sprinkling around the poles gives me small green spots in the midst of brown grass. Certainly doesn't seem wasteful of water when compared to people on my street watering their entire yards once or twice a day, primarily for looks.

[lwilg]

Obviously a typo in subject line!!

[jr 2]

this type of sprinkler do you find it just about anywhere???sounds like it is a big help as far as temp;;;jr2

[flyin-lowe]

Humidity is important also. I don't know if your gauge measured humidity and what is often called a heat index. It could be 90 degrees with very high humidity and be more problems for the martins then 100 degrees with low humidity. Almost everything I have read on here says misting is OK if the mister is away from the gourds so the martins can fly through it but having it misting on the gourds could be bad, even if the actual temps drops a few degrees. Most people who live in states that have high humidity will tell you it can have a huge impact on the heat index.

[lwilg]

I can see where very high humidity could be a problem in terms of the heat index. Our humidity here was 53% today. If the humidity inside the gourd today was 62% and the temperature inside the gourd was 93, then the heat index would have been 109--the same temperature as the gourds without sprinklers.

Would the heat index of 109 and the actual temperature of 109 have the same impact on birds since birds have a different cooling system than humans?

Here, having birds flying through a sprinkler to get to the gourds would be worthless since it is the birds in the gourd that are the ones dying from heat.

[lwilg]

you can find the materials at most nurseries, lowes, etc. in the drip irrigation section. I do not know whether this system is ok in areas of high humidity, as one person noted. I just know that in south central kansas last year I lost 1/3 of the birds in the gourds in the heat wave before I put up the sprinklers. I lost none after that. I had 1 dead bird in 1 gourd this year out of 70 that hatched.

[Guest]

After 5 yrs of trying to get our colony back up and active, we finally have 5 of six gourds with nests and babies. I've been misting with cold well water the last couple days. Temp is 96 (feels like 104) and relative humidity at 44%. I hope this works. I just have to have some successfully fledge so I can count on having my pm's back next year.
Will do nest checks tomorrow to see.

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[lwilg]

Rita--I hope you have good luck with misting. It certainly has worked for me here in Kansas. I know some think misting is dangerous in high humidity areas. I checked with a local ornithologist who said he was unaware of any studies of the impact of high heat indexes on birds, but doubted any significant impact because birds cool by panting, not sweating. I have hoped someone on the forum would be able to shed some light on this issue with examples, or evidence of some kind. So far I have seen only assertions that there is a negative impact but I can't find actually evidence/examples on the forum that support these assertions and I can't find any info online either.

[Louise Chambers]

I don't think anyone said it's bad, but have repeated to use it with caution, as higher humidity can be worse for the birds. Here's a thread with some info:

http://www.purplemartin.org/forum/viewt ... y&&start=0

[jeffwilliams72]

I have been misting for the past 4 days, temps are around 105 and humidity is 43%. I have 2 sy nests that have been hatching thru this heat, and 7 other nests with older babies. At the end of the day, I take down the mister and all of the babies seem to be in excellent condition.
Yesterday I walked under the racks during the peak heat of the day to check my mister, adult PMs flew out of almost every gourd, including gourds that were not nested in. They had to be in there for relief from the heat. In the days before we hit 100, the only ones I saw around were the ones with very tiny babies feeding them.
Since I started misting PMs are here all day, preening in the mist, and hanging out in the gourds.
However, my gourds are turning rust color from the hard water. Does anyone know what product might work, to remove the rust from the gourds at the end of the season???

[lwilg]

Louise--thanks for pointing out to me, correctly, that no one had said it is "bad." My statement about "negative impacts" was an exaggeration of the "cautions" being suggested. Sorry.
Thanks for the url to a thread on the topic.
I think it would be great if someone could actually do a study on how much the humidity inside a gourd is raised by sprinkling the outside of the gourd. How much, if any, would the humidity rise in a gourd above the natural humidity in low and high humidity parts of the country?
Thanks

[Louise Chambers]

I found this too, I thought Penny had provided some info:

TX Rehabber

Thu Jun 28, 2012

If you look at the physiology of birds, they do not have sweat glands and their only way of cooling themselves is by using shade, bathing or puffing out their feathers to dissipate the heat. They get rid of extra heat by using their respiratory system thru evaporation. This is the only option for baby birds.

The lower the humidity, the more moisture the bird can evaporate off of its respiratory system and the more heat that can be removed from the body. Conversely, the higher the humidity, the lower the amount of moisture evaporated from its respiratory system and the lower the amount of heat removed.
_________________
Penny Halstead

So the question may come down to, does misting raise humidity inside the nests? I would guess not unless used when it's already very humid outside - but guesses aren't worth much. But I think the info is good to have just the same. It might help us be aware of more factors that affect the birds.

[jedin]

JeffWilliams,
Try "ironout"? Works on many surfaces.

[jeffwilliams72]

Thanks jedin, I will try it!

[DornCounty]

I found this too, I thought Penny had provided some info:

TX Rehabber

Thu Jun 28, 2012

If you look at the physiology of birds, they do not have sweat glands and their only way of cooling themselves is by using shade, bathing or puffing out their feathers to dissipate the heat. They get rid of extra heat by using their respiratory system thru evaporation. This is the only option for baby birds.

The lower the humidity, the more moisture the bird can evaporate off of its respiratory system and the more heat that can be removed from the body. Conversely, the higher the humidity, the lower the amount of moisture evaporated from its respiratory system and the lower the amount of heat removed.
_________________
Penny Halstead

So the question may come down to, does misting raise humidity inside the nests? I would guess not unless used when it's already very humid outside - but guesses aren't worth much. But I think the info is good to have just the same. It might help us be aware of more factors that affect the birds.

sounds like a good formal test to add to teh PMCA list of things "to do" at some point. shouldn't take alot of capital.

[Peggy Riley]

Like Jeff said Ironout or Rustout will work. I have the same problem from last year and I've decided on just leaving them as is. They have bleached out a little this year.

[lwilg]

Louise--I have a couple small hygometers. I am going to try to do some testing inside my gourds since I still have the sprinklers up and will not be removing the gourds for a couple weeks. How much variation we will get in ambient humidity is not certain. We can get fairly hot and high humidity days here in southern Kansas, but probably not as much humidity as some people experience east and southeast of us. I will try to run tests as accurately as I can this year, and maybe next year too. I will report to you whatever info I discover. Maybe if others in the organization or the PM association set up some tests we can come up with data that will help people made decisions on the issue.
Thanks for the quotation you included. It sounds logical that humidity would impact evaporation when panting. Is it pretty well established that it is evaporation that does the cooling when birds pant, or could there be some other mechanism operating to cool when panting? Thanks

[Louise Chambers]

I think the panting cools through evaporation, that's what I remember from ornithology but will look for other data later this week. Thanks for collecting some data, that could be helpful - for everyone to contribute data for comparisons, everyone would likely need similar equipment and set-ups, but it will still be interesting to see what findings are from different locations.

Landlords will probably want to consider a variety of cooling methods, depending on type of housing they use, their region and typical summer temperatures, etc. This heat wave has been extreme and broken many records, hopefully we won't see similar weather next year. Using insulation, ventilation. shade, evaporative cooling, can all be very helpful tools, and since extreme heat can mean food is scarce, supplemental food might be helpful too.

[Don & Danielle]

Just to throw in my two cents....

I wonder if there's a difference between "misting" and "sprinkling". In my mind, misters put out a fine mist that I could imagine easily entering an opening in the housing. If the house wasn't venting very quickly, maybe the humidity would build up to levels that are too high. Sprinklers put out bigger drops of water, that would (maybe?) tend to just run down the tops & sides of the housing. Would this provide similar cooling to the inside of the housing? If the house was well-vented, would the humidity build-up be lessened?

Also, I wish I could read the minds of the parent PMs. To me anyway, there seemed to be lots of insects around here during the hot spell - dragonflys galore. But a couple of my nests appeared to be virtually not fed during the heat. Don't know why.

Lots of variables. Wish I had the time & brain-power to sort it all out.

[lwilg]

I think, as is suggested, that both misting and sprinkling need to be evaluated.
Certainly neither of these should be the only options. Most of the methods, such as shading, probably should not impact the birds as misting and sprinkling could possibly do. Different protective methods need to be devised to suit the environment, owners, and birds.
As Louise noted, the ideal would be to have some type of standardized system to do the evaluation. I don't know who might organize, support, and evaluate such a study.