Friday, January 28, 2011

2010 Nesting Season

2010 was a very interesting season. We all hope for a successful nest and look forward to observing eggs hatching, nestlings growing, and their first flights. It's always disappointing when a nest doesn't produce young. That said, this was a very interesting nest to observe, with a great cam!

Nesting Dates

First adult: 3/27
Eggs: 5/16, 5/19, 5/23, 5/28
Female last seen: 8/26
Male last seen: 8/28

After a month spent coping with intruder and territory issues the resident pair claimed their nest. It was amazing to watch the nest go from bare to huge in less than 2 weeks, in fact, so large the cam needed to be adjusted!! The Ospreys wasted no time getting down to the business of eggs.

The female did not incubate the first fact, she didn't incubate the entire season, she did, faithfully, stand guard from the nest perch.

The male started incubating after the second egg was laid. He continued to incubate the eggs until 6/18...the first egg was at day 33 (osprey eggs hatch between 35 and 42 days). The male behaved exactly as he would in a 'normal season'. He incubated, brought in nesting material and fish for the female. Interesting, when he realized the female was not incubating, he began covering the eggs with nesting material before leaving to fish. Covering the eggs made it difficult for observers to decide how many eggs were in the nest, but gave the eggs extra protection from predators...a very good male!!

After he stopped incubating he continued to bring fish to the nest, for the entire season, as he would if there were young to care for. The female continued guarding the nest, as she would have done with young in the nest. The male also continued, for the entire season, to bring nesting material. This is unusual, adding nesting material stops when the nestlings are getting ready to fledge. This may have been an attempt to secure his claim on the nest for next season.

The female's migration date was about 2 weeks after the young would have fledged, a normal time for the female.

The male's migration date was 2 days after the female left. This is the normal time he would have started migration after his last juvie migrated. The difference is, the female was the one he fished one to fish for...migration.

I do believe this is our past seasons resident pair(98% for female, 100% for male), there were 4 eggs, and the late start was caused by intruder/territory issues resulting in the nest not producing young. I've changed my opinion several times on the number of eggs, identifying the female and male, and the cause of a late nesting. At the start of the season, there were very few sightings of ospreys on the nest, and those were brief. A challenge for sure, a learning opportunity, absolutely. After many hours observing the nest, on cam and on site, reading posts from experienced cam observers on 3 forums, and comparing 2009 nest pics, I believe... past resident pair...4 eggs.

I encourage anyone that followed the nesting season to post any observations, photos, questions or opinions.

Head Marks 2009 & 2010 (click to enlarge)

On the issue of how many eggs, this is a pic posted on the Hancock Forum, by member BET, 5/31. I have pics from 5/28, but BET has the best.

We can now look forward to our Ospreys returning to their EGG READY nest, for a great 2011 season!!!


Sunday, June 13, 2010


The first egg will be 35 days old on 6/20, that's when we start watching for a hatch.   It's very unlikely these eggs are viable.  If they do hatch the next issue will be how the chicks are cared for, and that could be a problem.  The male has been doing all the incubating, as well as fishing for himself and the female, an unusual situation to say the least!!! 

If the eggs hatch the chicks have to be kept warm, fed, sheltered from sun, rain and predators.  This takes team work.  Maybe, hopefully,  if the female sees chicks something will "click in" and she will care for them, that's a big maybe.  The male can't fish and care for newly hatched chicks, and the female just standing in the nest, as she has,  won't be enough.  

Some cam viewers may have observed what appears to be intruders, again.  This is not the case.  There are Red-winged Blackbirds nesting in the bushes below and around the platform.  They now have their fledglings on the ground and are pestering the ospreys, which they consider a threat.  For the ospreys this is like having a mosquito buzzing around your room at night, and it should end soon.

There have been two new nesting platforms erected in the area, by the local utility company Nstar.  One at the Bike Path near Oyster Pond and one on Mill Road near Salt Pond.  Both platforms have been claimed by new males and they are busy adding sticks, this is keeping things peaceful in the area.  The male in the Clark building nest has settled down, he may have a female on the nest.  So, we now have seven nests in the area, between Fresh River Road and the WHOI cam nest,  three more than last season.  Cam viewers, not familiar with the area, can Google map it.

Some have been asking about human trash in the nest.  Trash in osprey nests is always an issue, but not much can be done about it.  Ospreys bring it in, take it out, bury it under sticks and sometimes the weather takes care of it.   Sadly sometimes it becomes a danger to both adults and chicks,  we can only watch for trouble and try to help when need.  I was at the nest yesterday, the blue rope is now in the bushes under the nest, but likely they'll bring more, it's an on going issue.  Osprey nests in the Mid-West, North-West and UK have baling twine and mono- filament fishing lines brought into the nests, trapping many ospreys.  Trash left in the nest at the end of the season,  if not blown out by winter winds,  is usually covered by new sticks at the start of the season….then new trash is added!!!

Well, let's see what happens over the next couple of weeks, stay tuned.


Monday, May 24, 2010

Now We Have A Great New View!

Hope you're all enjoying the newly-shifted camera angle - we made our move when the opportunity arose and got it done quickly!

Jazzel wanted to add a few thoughts about the state of the nest, and whether these birds are new or past residents! Here are her thoughts:

I'm very sure, now, after comparing countless pics of head markings, that these are the original resident WHOI Cam Ospreys. It's very difficult to compare pics from the old cam and new cam.

The intruder issues on the WHOI nest, this season, have been well documented by many cam viewers…both in commentary and pics.

Below is Dr. Rob Bierregaard's answer to questions I had about the intruder issues in Hilton Head, SC, Cape Coral, FL, this season and Conanicut, RI and Cape Henlopen, DE, last season. I posted this on the Hilton Head blog.

"I don't know exactly how long they have to get going. We've had young fledge in mid-late August on the Vineyard, so that pair probably didn't lay until late May. It may have been a renesting after a lost clutch, or it could have been one of these turn-over in the breeding pair situations, which very often result in no nesting for that year. I suspect that most of the intruder situations occur when one of the adults doesn't return and the fight to fill the vacancy is really protracted because none of the contestants has the psychological advantage of having been there the previous year. "Home-court advantage" is really a big deal in birds.

Eggs are produced about 2-3 days apart (more if the female is not in really good condition). I suspect that they could recycle only if it's really early in the nesting season. Whether they recycle or not would depend on physiological condition, and what the levels of estrogen were in the female's blood."

Looking back at nest caps, I don't believe there was a third egg….but I have more screen recordings to check.

The male is doing the incubating. But part time incubating will not result in a hatch.

The intruders are not an issue now...but they were at the start of the season, resulting in a very late start for the resident pair. It makes perfect sense that the male would incubate and fish...he would be doing this, at this stage in a normal season. It also makes sense that the female is not incubating, consider what Dr. Bierregaard said about the females estrogen blood level...

As I said, I believe this is the resident pair from past seasons. Someone commented this may be a young female accustomed to fish deliveries to the nest just waiting to be served, and to inexperienced to understand incubation.

A "young inexperienced" female would be three or four years old, and fishing for herself since her first migration, she would also be fishing for herself until her eggs hatched, while the male took over incubation duty. I think she's simply guarding her nest.

There are many ospreys in the area...including the new nesting pair on a building 500 yards from the cam nest, and more young ones arriving...a distraction, but not a intruder take over issue.

The WHOI pair are guarding the nest...insuring their claim for next season....note Dr. Bierregaard's comment on "Home-court advantage"

Hope this helps. This is a great learning experience..take notes : - )

Please comment on your observations.


Tuesday, May 4, 2010


Three issues have contributed to the cam nest not producing eggs, so far, this season.

The first and most important is the resident male did not survive migration. If the male had returned the hawks wouldn't have been a problem. He would have started repairing the nest and defending his territory.

When the female returned she had to choose a new mate, which she has. The new mate now has to establish his territory rights. This is a second issue because another young male is building a nest on a roof top 500 yards from the cam nest. This young male has also been trying to attract a female and establish his territory.

This courtship display is great to watch, but very distracting for nesting pairs. The male flies over his nesting ground with a fish, very high up, circling , hovering and calling, then drops down in a steep dive then returns to his previous hight, then repeats. The display attracts unattached ospreys, both male and female to the area. Hopefully he will find a mate this season, but he may not until next season.

Last season I watched a young male starting a nest in cell tower. Actually, he built three nests, he had that tower covered!! He also had to fight off other males that wanted the site. He did win the tower, but didn't have a mate by the end of the season. This season he returned, now has a mate, they are incubating.

I haven't observed the hawks showing any aggressive behavior toward the ospreys for well over a week. This may be because their nest failed, or they're just to busy hunting and feeding chicks. They are of course still there, just not a problem now.

From my on site observations, yesterday afternoon, the bachelor osprey seems to have a female prospect. She was on his nest several times, hopefully she'll stay and keep him busy!! The territory issues will continue, but should become less intense if he has a mate.

The cam nest pair spent most of the afternoon on the nest, nest perch ( she seems to like it ) and perched in nearby trees. The male brought in some nesting material, and they even did some bonding. There were a couple of territory incidents, but basically a quiet day.

Today started out very well…the male bringing in a lot of nesting material. Now, as I'm writing this, there's an obvious battle in progress….stay tuned…


Monday, May 3, 2010

Hanging Out at the Nest

Well, it looks like we may have some activity at the nest for the season. There have been several sightings of a pair on the platform recently and in fact, one is sitting on the perch of the nest as I write!

At this point, it seems as if the birds in the area (there are others attempting nests on another building here at WHOI!) are preparing for next season. It makes us sad to know that we probably won't be seeing youngsters this year but are hoping for the best, no matter what!

Many of you have sent in pictures of the birds and we appreciate it. We'll be posting some examples on here soon.

Monday, April 19, 2010

Birds on the Nest - For a While at Least!

Son of a gun! 10 minutes after Jazzel came by to look into rumors of a nest elsewhere on the WHOI campus, a pair decided to take a seat on our nest for a while! Jazzel is going to post her observations, including how the male 'mantled,' later but here's a picture to prove that we actually had birds for a while today!

Thursday, April 8, 2010

So, Where ARE The Birds?

Lots of people have been emailing us lately wondering why there doesn't seem to be any birds on the nest when they look at the camera.

That, osprey fans, is the million dollar question facing us right now - or at least more than a few dollars question!

The bottom line is that as of right now, no osprey have taken up residence in the nest. Even though I can hear one call out as I write this from my desk, they haven't begun the rebuilding process.

And believe me, no one is more concerned about our lack of residents so far than the staff here at WHOI, who spent a lot of time, energy and yes, money, to get a new camera, website and blog up and running (sometime down the road we'll do an entry on the effort it took over the winter to make this all come together.)

Here's our best guess so far as to why there are no residents, beyond the pure fact that nature is fickle!

About two months ago, a pair of good sized red-tailed hawks started hanging out in the area, hunting small rodents in the area field grass and marshes, and they seem to have decided that this is not such a bad place to spend time! They liked to sit on a nearby radio tower used by researchers or a flag pole overlooking the softball field at the Quissett Campus of WHOI.

Eventually, they got up the courage to sit on the perch attached to the nest, and I think that's when they really decided that real estate on the Cape is prime!

Fast forward to the arrival of two osprey the last weekend of March and that's when all bets were off and what appeared to be a reenactment of the Battle of Britain began! Lots of swooping and diving, games of in-flight, well, chicken, for lack of a better description and a lot of chatter between the pairs. The osprey would seem to prevail, then come in to the nest and hopes would rise, but they would take off just as quickly as they landed:

Now, there's barely any activity at the nest at all. Yes, there are osprey in the area but none have decided to take a chance on the nest. And those red-tailed hawks are still hanging around the area - looking, to us, like the bad guys on the block!

So that's our best guess. We're hoping that an osprey will take a chance - if not for this year, in preparation for next (which we don't even want to think about!)

What do you think is the reason the osprey nest is looking lonely these days? And do you think we'll have something to look at this season or do we now have the best looking empty nest on the East Coast!