Wednesday, May 29, 2013

What is it about Ospreys?

What is it about Ospreys that is so captivating? They have caused me to spend 20 years studying them, to devote my life savings to this effort, living below the poverty level in order to keep visiting over 90 nests in my eight county study area here in Minnesota. And I still can't fully explain my love for them. No other bird captivates me like this. It remains a mystery...but I see that I am not alone! It's so wonderful to connect with people all over the world who understand this love and who have been supportive of what I am doing. Thanks to all who share this passion. I appreciate those of you who contact me out of concern for some bird, some nest...I am happy to do welfare checks. I love running into some of my volunteer monitors in the field, and being greeted with such enthusiasm. I love the nest hosts who call me with interesting observations, concerns. Thanks to all who help me watch over these raptors...it takes a village!

Monday, May 27, 2013

I was watching a male in a tree eating a fish, as the female on the nest was food begging vociferously. He ate the whole fish and then preened a bit, as she continued her cries for food. Finally he flew off and came back in less than two minutes with a fish for her, delivered it to her and quickly took over incubation duties. Males must feed themselves first, not out of selfishness (an anthropomorphic projection of human motivation) but so they can remain strong enough to be a good provider.
On the other hand, I was watching one of the nests whose male is caring for two females on two nests. He was eating a fish as one of his females was soliciting food loudly...and half way thru his fish he delivered the remains to her. She left with it and he took over incubation duties, but within a few minutes, he jumped up and flew off. She was not done eating, but had to return to the nest, bringing the fish with her. She dropped the fish remains on the edge of the nest and resumed incubating. It's what she has to do. This must be getting difficult for both females, who do not get enough food, enough time away from incubating. It will only get worse when the chicks hatch and he could potentially have eight mouths to feed...if there are 3 chicks and a female on both nests...in addition to feeding himself. I am hoping for some very small broods and some females that are willing to hunt.

Wednesday, May 22, 2013

Another cold misty day...

I spent the day checking nests with one of my most dedicated volunteers. We have a great time and always find something new and interesting, exploring back roads. We read some bands, some escaped us. We found a pair who had been driven off their nest by human activity safely settled somewhere not too far away. I had to confirm a band I read earlier...after checking the band list and realizing it was a new male on the nest, and the male from last year appears to have been replaced by his brother! Seemed like too much of a coincidence, so I reread the band to be sure. Yup, that's what happened.
A productive day in the cold, gray mist. Thanks again to ALL my nest monitors. I appreciate each and everyone of you who shares your observations throughout the season. I couldn't do this without you!

Sunday, May 19, 2013

Nest failure

Another interesting day in the field. This is the time of year that we start to discover nests that have failed for one reason or another, and that is what happened today. For several weeks I have been visiting a nest and finding an extra male harassing the incubating pair. The unbanded male interloper was there most of the time, trying to land on the nest, perching nearby, doing a sky dance, and both the male and female would leave the nest to chase him away. I was there a week ago and this scenario was playing out again. Today the residential banded male was nowhere to be found and the female was no longer incubating. She just perched nearby, preening. Then she was joined by the unbanded male. He behaved defensively, turning his back to her and shaking his wings occasionally. Other times they just preened near each other. No vocalizations, no chasing. I was there for nearly three hours and did not see any incubation or the banded male. Wish I knew what actually happened. Perhaps a new frustration nest will pop up in the area, or I will find the banded male elsewhere. Hmmmmmm.
Sometimes I can figure out why a nest failed. If they incubate too long we know the eggs were infertile. Sometimes the behaviors of the adults give us clues. A sudden abandonment can be due to predation. Storms and hail can damage eggs. I am not sure what happened in this case. I do not believe a new male would easily run off the territorial male mid season. Did something happen to the banded male and the new male is just taking advantage of the opportunity to take over this territory? Hopefully further visits may offer some insights.

Sunday, May 12, 2013

"Divorce"

I have documented two "divorces" so far this year. Pairs where both are alive and well, but moved to another nest with another mate. Usually the split occurs after a failed breeding season the year before, and that is the case with both these pairs. I was watching one of the new pairs today...a sweet new bond forming. The new pair were sitting on the same branch in a tree in the late afternoon sun. Both were calm and peaceful. The male kept walking a few steps closer, sitting for a while, then a few more steps in her direction until they we sitting side by side, almost touching. Then just preening and snoozing comfortably together. She is small for a female, and he is a handsome male, with a totally white breast. Nice.
We also have a pair that is sharing their twelfth year together. That's is the longest known pair bond so far in this study.

Thursday, May 9, 2013

May 9, 2013

Another day in the field, and 178 miles! I visited 21 nests...not all I had hoped to get to, but still a productive day of data gathering. Out of the 21 nests, 13 were incubating. I read five additional bands. One osprey, nesting in a very difficult spot for band reading, was found perching in a low, easy spot and I got his band read quickly once I noticed him in the trees. My sincere thanks to him! Oddly, several nests where I had observed ospreys before were vacant today. There is one pair that is moving around, seen here and there, but just not ready to choose their nest and lay eggs. A few others are settling in, but have not popped out any eggs yet. I found one female who has moved to her third nest..After repeated nest failures, she keeps swapping nests and swapping mates. Hope this one is the right one. The pair who seemed to fighting a pair of eagles for their nest, are back on the nest. No eggs. Other ospreys seen there too, so I am searching for another nest in the area. I have to be a bit of a detective to figure everything out, and to find new nests. Please do let me know if you see ospreys dropping sticks anywhere!
And if anyone out there has a huge telephoto lens and would like to help me get a difficult band read, let me know. I mean REALLY long...and still we will have to blow it up. But it might be easier than me sitting for hours and hours and waiting for this bird to sit still where I can see the legs. That moment when they come in for a landing, with both legs dangling, might just reveal what I need with a fast, long lens. I came home to a sweet phone message from one of the osprey nest hosts, telling me the birds had laid their first egg. Nice. Thanks to everyone who helps and supports me in this work, in so many different ways. Deep appreciation on this end.

Eagles eagle eagles

It's been hard for me to keep up here...lots of interesting things happening. Eagles are proving to be more of a problem than in the past. With the increase in the population of both species, it's not surprising that the conflicts are also on the rise. One nestpole host contacted me to report that the ospreys were gone and eagles were on the nest. But the ospreys have been seen again on the nest with eagles perched nearby. It remains to be seen who will end up on the nest. Eagles used to be considered to be sub canopy nesters , while ospreys are super canopy nesters...but apparently that is no longer necessarily true. The nesting choices of most ospreys may provide greater protection from predation. Many nests are incubating now, new nests are popping up. We also have one male who is shuttling back and forth between two nests and two females. It's happened before, and one female will end up getting the short end of the fish. I suspect one nest will fail. I am also observing a great deal of disturbance from other ospreys too! Too many ospreys fighting for territories and choice nesting spots. As the population increases it also provides greater opportunities for extra pair copulation. Mixing up the gene pool. I am plugging away at reading bands but some ospreys are just not cooperating! Nor is my old car...an expensive repair has slowed me down a bit.

Friday, May 3, 2013

Snowy day in early May

I spent this cold, snowy, and wet day checking osprey nests.  I drove 139 miles and visited  23 nests. Ten of those nests were incubating.  Seems that a lot of ospreys laid eggs in the past week.  A few nests that had one or more birds in them  last week, were empty today.  I also found a female from another state, which one I am not sure, but she had a different color band than is used in Minnesota. Very hard to read. I will figure it out tho! I watched a number of females sitting on the eggs as the snow swirled around them like a snow globe, with no males anywhere in sight. No fish deliveries, no relief from their duties. And unfortunately , no chance for me to read the males bands! The sleet pelted my face as I moved between two close nests for 2.5 hours, hoping to get the males bands read. Skunked.
Still, it was oddly enjoyable to be out there silently observing the unfolding of this strange spring. I watched a great horned owl and her large chick sitting side by side on a nest quite near an osprey nest. GHO's are one of the main predators of ospreys, so this is slightly discomforting. Sometimes they coexist peacefully, sometimes they sequentially kill the osprey chicks. They can even kill an adult osprey.
At the last nest I visited I witnessed a bald eagle relentlessly chasing and dive bombing an osprey, with some serious aggression on display, and it went on as far as I could see...until they disappeared over the horizon. 
I also received a generous donation today from Debbie Engelmann. I am so grateful for the financial support as well as the kind words of encouragement for what I am trying to do. It means so much to  me to know that there are those who understand the amount of effort involved and the value of this research. I couldn't do it alone. A million thanks to Debbie for all she has given to this project.