Friday, March 27, 2009

Charlotte Leaves the Egg/Eggs Uncovered and Some Answers About Kay and Jay of Tulsa

A Tulsa Neighborhood Fox Marks Territory With Urine

In my quandary as to what in the world was going on at the Tulsa nest with Kay calling and calling for food and it seemed that Jay wasn't bringing her enough, I asked some questions of the Tulsa Hawkwatchers.

Cheryl Cavert who has taken some great photographs of the Tulsa hawks, sent me a response which was instrumental for a partial understanding about what has been happening in Tulsa.

Keep reading for some answers from Cheryl who is one of the few members of the Tulsa Forum who is close enough to the nest to actually see the hawks live--

With regard to food sources in the area, I have not noticed any difference in the pigeon population around the nest. The nice neighbor next to the tower has at least 4-6 bird feeders up that are always busy - I always see squirrels and pigeons there as well as an assortment of smaller birds. I will try to pay more attention in the coming weeks to the pigeon populations that I see perched on the nearby business rooftops.

With the kind of weather we have been having (well, that does not excuse Jay totally on the beautiful warm spring days we have had!) - high winds, rains, hail, snow - that may have more to do with what Jay is bringing - or not bringing! - to Kay for dinner.

We have had a number of days with extremely high winds (30-40 mph gusts) that I imagine would make it dangerous for the hawks to fly. Landing on the nesting platform would be like trying to thread a needle outside on a windy day!!

So my uninformed theory is that Jay has been playing it safe. I have not been able to spot him anywhere - I have only seen him perched on the tower 2 times in 2 weeks and not a single spotting in a tree! - so he has been hanging out in a more protected spot. I am certain that is why earlier this week Jay was not seen for almost 2 days - the winds were atrocious - nothing was out flying and if anyone did they ran the risk of being flattened against a building!

I live just a little over a mile south and east from the KJRH nest and there are lots and lots of bunnies out - the earliest by 2 months that I have ever seen little ones already out. A couple of weeks ago I rescued two baby bunnies from my garden and put them in a safer place (away from my cats who were helping me garden and in an area with plenty of cover). The next evening we saw a red fox coming trotting across our yard with a bunny in its mouth!

A couple of evenings later my husband heard a cat fight commotion and looked over and one of our cats was chasing the red fox out of our yard (he was not happy the fox took his play toy a few days earlier!). Needless to say, the cats are not going out much anymore and when they do they stick to my side!!

I will send you a photo of a red fox that I took a couple of blocks away a couple of weeks ago. I do not know if it is the same fox or not. I have seen a fox off and on in the area for several years, but lately my number of sightings has increased.

A couple of blocks to my south is highway construction/ major overhaul of drainage/sewer systems, so it has been torn up for over a mile to the Arkansas River - disrupting lots of wildlife.
Cheryl Cavert


You filled in many of the blanks I've been trying to fill in the last week or so. Excellent information on the prey levels. Including that there are pigeons and squirrels which are worth an RTs time to hunt at the handy feeders. Dinky birds aren't really worth the caloric effort they take to catch. Often a lot of energy has to be expended that may not be recouped from the meal.

I've seen Pale Male sneak up on a juicy Robin but much smaller birds, unless it is a tempting tidbit for Lola specially, he doesn't often bother with. Urban Red-tails have adapted to urban prey but in the country, they don't take many birds, it's 95% bunnies, voles, mice, and other rodents. In Wisconsin I see songbirds sitting on wires with a Red-tail on the nearest pole, and nobody is getting eaten.

I knew that there was bad weather in Tulsa but you gave me the important specifics about that weather. Extremely important as the term "bad weather" can mean many things, some much worse than others. I now can understand why Jay might be hunkering down somewhere instead of hunting. Besides, unless the prey is capable of being out in the "bad weather" it is difficult for Jay to hunt them.

Also important is to know is what the wind was doing and knowing it, gusts of 30 to 40 MPH, I know they were very dangerous to birds. I think you're right, it would have been difficult for Jay to make the trip safely on those days.

Urban birds of all stripes, from pigeons to hawks, are injured by being smashed into buildings. I've set a number of pigeon wings after we've had high winds. I also theorize that the broken beaks of some of the urban Red-tails were gotten by building collisions. Landing on a TV tower nest at that height could be chancy. And we have to remember that Jay, being lighter, and with less strength than Kay, is more easily blown around.

Brett Odom has seen Pale Male Jr. repeatedly miss the entrance to the nest shelf and get smacked into the building while attempting to enter the entrance to the nest.

Though we do have episodes of Jay making it to the nest but not bringing prey. Remember the evergreen bough Kay was so dissatisfied with? Was all the prey hiding from the weather and therefore Jay had nothing to hunt?

You're right again, it doesn't excuse Jay on the days when the weather is fine and Kay calls for food that doesn't come. That behavior on Jay's part is still a worrisome mystery.

I'm fascinated that the fox stole the cat's toy. Which kind of cat toy was nipped? Great idea to keep the kitties in the house. I never let mine out these days at all. Though previously I'd "walk" them on a 6 foot lead, short enough to keep them from predating the birds and making them near enough to me that they weren't predated by somebody else.

Most fox and their predator counterparts aren't going to walk up within 6 feet of me and grab my cat.

Though I knew a gentleman in California who was standing next to his pool with his Malamute on the other, when a Mountain Lion, leapt his waist high pool fence, grabbed his dog by the neck, a Malamute, killed it deftly , pulled it over the fence, and went back into the woods with his dead dog. He said he missed his dog very much but if you're going to live in the woods, you can't fault the Mountain Lion from doing what Mountain Lions do. I concur.

And there have been a number of episodes in which a raptor has grabbed a pet parrot off an owner's shoulder.

Care must be taken mustn't it?

A GREAT QUESTION FROM BRETT ODOM, chief hawkwatcher of urban Pale Male Jr. and Charlotte's New York City "shelf" nest.

"In your experience, is it necessary for the eggs to be incubated at all times? Twice today Charlotte left the nest unsupervised for over 10 minutes and with the temperatures at a high of 54F this has me a little concerned."
Brett Odom

It depends on how much over ten minutes the lag was. I expect that it wasn’t that much over ten, yes? That is likely fine; particularly as this nest has unusual protection due to the glass which keeps cold wind down to some extent.

Also a thought, we’ve seen Charlotte go into the nest area late in the hot summer (Last year? The year before?) and raise her wings as if to cool off in front of an air flow from the vents. High summer=AC. Spring at 54F? The exhaust air would likely be warm from the heat running inside the building. This would keep the nest area warmer than the usual outside temperature. Plus there is the possibility of heat from the sun as it comes through the glass, warming the nest as well.

That said if the parents leave the eggs uncovered too often for too long and they cool, the eggs die.

There are two top causes for high egg mortality in Red-tailed Hawks.

1. Pervasive cold drenching rain, where the formel gets drenched clean through to her skin and can't keep the eggs warm enough and/or the cold water puddles so the formel and eggs are sitting in it. Puddling usually is not a problem in trees but it was a very possible problem (along with high wind) at the Trump Parc nest. That nest failed every year until the one year in which Jr. and Charlotte double clutched (the old eggs had blown out of the nest) very late in the season and we had a drought. Not much in the way of rain or high wind either and they finally succeeded. The next year, they failed again, and then they moved to 888.

2. The second big cause of failure is the formel leaving the eggs uncovered in the nest as she nor the male are getting enough to eat so they both have to hunt, leaving the eggs unattended. The Red-tail literature says that if the lag becomes 20-30 minutes and then there are repeats of this behavior, that that is surely trouble for egg viability.

I suspect that perhaps Charlotte hasn’t finished the clutch so partial incubation is currently on the menu? Your thought?

In the photo of the egg you sent previously, Charlotte is on the left carrying a twig towards the nest. Where did the stick come from? Had she gone out to get it? Had Jr. delivered it?
Donegal Browne

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