It’s been a busy few weeks trying to keep up with all the changes on our nests. Sadly, I believe we are heading for a record year regarding nest failures. We already have about 36 failures, probably more as I write. Last year we had 40 and the year before we had 37.....but this is still only June. One day last week I checked 24 nests and 11 had failed. Many of the failed nests are near each other. It becomes a real thrill to pull up to a nest and see three chicks motoring around on the nest...a real cause for celebration! Some surprises have occurred also tho. There was one nest that was clearly being horribly attacked by black flies, with the female flying off the nest over and over. I watched that nest one day for 90 minutes and I believe she was on the nest for approximately 15 minutes during that visit. I thought for sure that nest was headed for failure....but it did hatch successfully! I have come to the conclusion that eggs may survive longer periods without being incubated than I originally believed, if the weather is warm. But most of the nests where we observed adults struggling to shake off the black flies, have failed. There are many other nests where I cannot say what the cause for the failure is. Since the failures occurred during the time when we observed swarms of black flies on other nests, it may be related to that issue. I wish I could visit nests more often. Many nests are only visited every couple of weeks. One week they are incubating, or caring for newly hatched chicks, and at the next visit, the nest is empty. When I do the annual report, I will try to separate the failures into nests that failed to hatch and nests that failed after signs of hatching were observed, but without more frequent visits, I may not know for sure on many nests. I am continuing to find new nests, with two found this past week! I wonder how many there are that I dont know about! At any rate, having said all that, the black flies seem to have died off and many ospreys that survived the swarms, are much more comfortable now. This year has raised a lot of questions in my mind. I watched one nest, which has failed for five years in a row, and wondered why they stay at this site. Would moving to a new territory improve their chances of breeding successfully? Well my answer to all questions is to just keep watching, keep taking notes. Clearly this is going to be a tough year regarding our productivity rates, but as I keep saying, this is why we keep going. So few long term studies exist and being able to look at the data that has been consistently collected for 26 years maybe very useful in helping us understand this planet and the changes it is experiencing. On a happier note, it is such a joy to watch the developmental stages the little guys go thru...I was noticing how interesting it is when you see the chicks move from being entirely focused on a very small world which consists of their siblings and their parents, and each little bite of fish, to becoming aware of the world that surrounds them. Suddenly they are toddling off to the edge of the nest to look around at their world. They begin watching other birds that fly over, or even planes above. Their little worlds are expanding. They will move out into that world sooner than you think! These little friends of ours grow so fast.
Please report new Osprey nests to Vanessa Greene at Osprey.mn@gmail.com Volunteer to monitor a nest!
Thursday, June 27, 2019
Saturday, June 8, 2019
Nest failures....
I am back in town after seeing Paul McCartney in Madison....and very sad to report that it appears that the Arboretum cam nest has failed. I believe the newly hatched chicks may have succumbed to the swarms of black flies, or buffalo gnats, that we have been observing. There is an article on the front page of the Star Tribune about this very issue. They refer to the issue as approaching historic levels. The MMCD, who usually treats the black fly larvae, was unable to this year as a result of floodwaters. I have never seenanything quite like this and it’s disturbing. Another nest in the area of the Arboretum has also failed, and we suspect for the same reason. I will be checking nests this weekend....as many as I can, to see if others have failed.
(There are many more comments and conversations about this topic on our Facebook page).
(There are many more comments and conversations about this topic on our Facebook page).
I also hear that the Raptor resource project is observing black fly problems with eagles nesting in Iowa. Hoping for some dry, windy weather.
Wednesday, June 5, 2019
Hatching at the Arboretum cam nest
The first chick has hatched on the Arboretum cam nest...yesterday, In spite of the torment caused by the black flies. The cam lens is already covered with poop so it’s bard to see much, but I could tell by the adults behavior that hatching had begun, right on schedule. They are restless, sitting high and slightly hunched over, protecting the chick but trying not to squish it! I have not seen a feeding yet....and have to go to work....but will tune in later. We may get another chick today or tomorrow! Kind of creepy watching the black flies crawling on the cam lens! They look huge, but are really tiny. Hoping the chicks survive the onslaught. The adults have heroically withstood the torture to hatch their offspring.
Friday, May 31, 2019
Black flies
Things have taken a disturbing turn in the last 24 hours. Yesterday I was watching a nest and the female jumped up and flew off the nest repeatedly to fly loops, leaving eggs unincubated for 5-10 minutes or so at a time. I found this odd. I was standing outside with my scope on a tripod and was aware that there there was a sudden increase in bugs. They were crawling all over my scope , my head, flying into my eyes and nose, but I did not feel like I was getting bit. The previous two days it was bug free and pleasant to be out there in the field. I noticed the female was shaking her head almost constantly. She repeated this pattern of flying off many times. I finally left and proceeded to another nest. At this nest I found no one on the nest at all. Oh dear. Then the female finally returned, sat down in incubating posture for a few minutes and the suddenly jumped up and flew off. She did this over and over, flying loops before returning to the nest briefly. For over 90 minutes this continued. At one point she was gone for 20 minutes and came back with blood on her neck. I hope it was fish blood. She never stayed in the nest for more than five minutes at a time and was shaking her head constantly. I started to connect the dots between the observed behaviors on these two nests. Then last evening I got a report from someone watching the Arboretum Cam nest. Female would not stay on the nest. She was shaking her head constantly and you could see bugs swarming the nest. When I went to bed, the eggs were still uncovered. This morning the male was in the nest. Then I received another report of a female that would not stay on the nest. The monitors are very concerned, as am I. This appears to be a new hatch of black flies which are tormenting many ospreys. I don’t remember it ever being quite this bad, tho a few years ago, we had a huge hatch that caused a chick on the Arboretum nest to jump to its death prematurely, to escape the flies. This is coming at an earlier time this year when we have newly hatched chicks, or eggs about to hatch. The timing could not be worse. I have been observing today that some nests seem to be unbothered......those that are further away from lakes and who are higher up. On some very tall cell tower nests, I see a definite breeze and no head shaking at all. I am afraid that some nests may fail if the adults literally can’t stand to be on the nest. Black flies live for about three weeks, so those late hatching nests may be the lucky ones this year. This all may be related to climate change and the heavy rains we have had recently. It’s very hard to watch these tormented ospreys, but there is nothing we can do, but observe closely, document carefully. This is how we learn, and this is why we keep monitoring these nests for so long. Ospreys are an indicator species so the health of their population reveals much to us about the health of our environment. So monitors, pay close attention to behaviors. Head shaking and agitation may seem like a small thing but it may turn out to be critically important. Watch closely. For me these seem like dramatic changes in behavior. It’s even important to report the lack of head shaking! It may help us figure out which nests are more vulnerable to black flies.
We have had a number of nests fail in recent days....adults are just suddenly gone. Could it be black flies that drove them off the nest? Time will tell. As I continued to make some rounds today, many nests seemed to be fine, or only slightly bothered...not enough to cause them to leave the nest. The breezes picked up as the day progressed. That may help the situation. Fingers crossed for this to be a minor blip, but I encourage all Osprey nest monitors to pay close attention to the head shaking and how long adults are off the nest. Include this info in your reports.
Think good thoughts for our winged friends!
Tuesday, May 28, 2019
Hatching!
Our long wait is being rewarded ....our chicks are hatching! We have a couple of nests for sure, and many more will follow every day. I am STILL plugging away at reading the difficult bands. The sad news is that we are also at that stage where nests are failing. And many times I don’t know why. Incubating one day, gone the next. The only real explanation I can offer is predation. One of our new nests this year has already failed. I was unable to find any adults and this is troubling. I hope it was just eggs that succumbed to predation or the pounding rains, and not the adults that may have perished. I searched for bodies, feathers, some clues.....but found nothing. The homeowner that lives near this new nest is heartbroken. I understand. And I love how people do fall in love with these birds. There is just something about ospreys. We still have a few nests, with a pair present, but no eggs laid. At this time, it’s probably too late and hormone levels are dropping. But sometimes this occurs because the female is too young to lay eggs and they become what we call “Housekeepers”...working on the nest, establishing a pair bond thru feeding, but raising no chicks..
The new volunteers are learning the subtle signs of hatching. When one reports that the male brought a fish and the female took it and started eating, IN the nest.....this is often a sign that she has wee ones to feed, tho we can’t see them for a while. Those little guys can’t stand up and are not visible above the nest edge for a little while, but we can observe the changes in the adult behaviors...restlessness, getting up to look down into the nest cup, eating on the nest and offering small bites to the little guys. Males also often stick closer by, and seem to enjoy watching the feedings....some will even help with the feeding. Can’t wait till I get to see the first bobble heads!
Tuesday, May 21, 2019
Another cold gray day...
Another interesting day with the ospreys! It was yet another gray, chilly, blustery day here in Minnesota....just the kind of day I like!!!! Unfortunately it started with needing to buy new tires. All the driving I do wears them out quickly. Then I visited a nest that I have been to so many times this year and I have not been able to get the males band read. This nest has had a banded pair for years and the female has been very accommodating, over and over, revealing her bands.....but the male is always incubating or gone! I have checked and rechecked all his favorite perches, used in the past. This has made me wonder if it could be a new male. But they were one of the very first nests to lay eggs, so that often indicates an old experienced pair that got down to business quickly, as they know that the sooner they lay eggs, the greater chance their offspring have of being ready to survive migration. Hmmmm. I searched again, but could not find him, so I started to drive away and as I went down the road, around the bend, behind some tall trees, I glanced up and saw an Osprey perched very high in a very tall tree. I pulled over and put up the scope.....ahhhh there he was! A new perch for this male this year! I have probably driven under him many times. Trickster. Today he said, hey Vanessa, pay attention! It made me laugh.
I drove past a few other nests to be sure they were still incubating, and came upon a pair incubating side by side. Always such a touching sight, one that I don’t see very often, but this kind of teamwork always warms my heart . (Forgive the crappy photo, taken with my iPad thru the scope.)
Then I proceeded to another nest where I have been getting skunked on bands. This nest has a new male. I know this because the male who was here last year is now nesting on a new nest across the lake. (This is probably a response to the nest failing last year.) I have spent many hours, many repeat visits, and have only gotten a glimpse of one digit on his band. He, too, is either incubating or gone and I cannot find his favorite perch. I watched as he sat in the nest while the female preened on the nest edge. She finally moved closer and began food begging quietly, and he jumped up and flew away. Damn. I never get a good view of his bands. He headed towards the lake, so I followed. Unfortunately, it takes me longer since I have to zoom along these winding roads! I got down to a boat launch to find about five people fishing. I opened my window and grabbed my binoculars to search the lake.....jackpot! TWO ospreys fishing! I suspected I knew who both of these males were, but which one is the one I am trying to identify? It was SO windy, and the water so choppy and gray. None of these fishermen even looked up at these two magnificent birds flying above. My instincts picked one Osprey to watch...and he hovered, dropped into the lake but came up empty. He circled around and tried again in the same spot...bingo! He came up with a fish! So fast, so easy, in spite of the choppy water and strong gusty winds. These birds are so amazing! He circled back towards the shore and dipped low behind some trees. I assumed he might perch there out of the wind to eat the head before he went to the nest, so I drove around looking for him. Could not find him, so I headed back to the nest....and he beat me there! He was making the hand off of the fish to the female and she went to her perch to eat. He once again took over the incubation duties. It’s such a treat to see them hunting, and to see a successful dive.....but I still didnt get his band read! As the winds picked up even more and the temperature dropped, a few spits of rain were beginning. Another day in the field comes to an end. It’s a good day when you get a few more bands read, see an Osprey incubating next to its mate, and witness a successful fishing attempt!
Wednesday, May 15, 2019
Did you think I forgot about you?
Did you all think I forgot about you? Forty lashes for me for not writing more often. This Osprey season is off to a crazy start, with so many new nests being reported or discovered, and it seems like the early days of the season have gone too fast. I love a slow start, with cool days, slow arrivals, time to read bands before incubation, and before woodticks....but that’s not the way 2019 is going. Most nests are incubating now and I am still trying to get the bands read. That can mean waiting for a long time for a bird to stand up and show me its legs. I visited a nest last weekend with two banded birds and it took me three and a half hours to get the bands read. Those of you have read bands may understand, trying to approach a nest slowly, wondering if one more step will cause them to fly off the nest. Trying to stand as motionless as you can, as your mind races...can I move a little more around this way or that way, or will the bird just raise his tail a little so I can see his legs, will he untuck his banded leg, will the clouds stop the glare of the sun. Where did the other one go? Should I move or will the bird move, will I miss my brief chance if I do move. My heart always starts to race when that golden moment arrives, the bird is in the perfect spot, the light is perfect, now just get the scope focused....got it!! Kind of exciting, but time consuming. Today I spent a lot of time trying to read a silver federal band on an Osprey, with nine small numbers all the way around the leg. These bands are primarily meant to identify a dead bird. The auxilary color bands, with two large digits, are meant for identifying a live bird from a distance. I am so damn curious tho, I stayed until I had six of the nine digits, but then she returned to her nest to incubate. Ahhhhhhh. I will try again, and I will get this one. Some others are almost impossible. I have a silver banded female on a nest on a very tall cell tower, and I am not sure I will ever get that one.
Ospreys are semi colonial, which means they like to nest near each other, so many of the new nests are in the neighborhood of other established nests. I am still learning about how close ospreys will nest to each other and our population is developing into definite clusters. As a result we are seeing increasing interactions with other ospreys. A few weeks ago I went out for a four hour walkabout with one of my volunteers, in an area with a growing cluster of nests. It was so amazing to watch all these ospreys flying around, some ospreys were seen as intruders and were chased off, while others caused no concern. We had a hard time figuring out which nest each Osprey belonged to! Thanks to all who have reached out to me , shared sightings, reported new nests to me, volunteered their time to help us out! More soon, I promise.
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