Osprey Cam Web Log 2006

Predators

Technical Note: I wanted to mention a quick technical note. One of our cam watchers asked why the Osprey Cam is not in color like the Eagle Cam. The Osprey Cam is a color camera, but when it is cloudy, it is hard to see the colors. Also the area behind the ospreys is rather brown at this time, so the colors on the cam image are rather muted. But the camera we're using is a color camera.

And while I'm talking about the camera, I'll mention another topic: Personally I've noticed that our infrared image at night is a bit washed out. We believe that this is due to the age of our camera, and we plan to install a new cam after the osprey family migrates south in September.

Nest Update: The osprey parents seem to be falling into a nice rhythm these days. The mother sits on the eggs the majority of the time (probably around 70%) and the father comes in occasionally to bring her a fish and to relieve her for a while so she can take a break.

Both parents also roll the eggs (about once an hour) to make sure they are evenly heated and to ensure that the embryos do not stick to the inside of the eggshells. The warmth that the parents provide is crucial to the proper and timely development of the small chick inside each shell.

During our big rain last weekend, we saw the female really wedging herself down into the nest cup and keeping a wall of nesting material around her to keep all the eggs safe and warm. Here you can see a photo comparison of the parent's sitting position from last year when compared to our parent last weekend during the heavy rains.

The parents have quite a challenge in keeping four eggs near their brood patch, which is the featherless area on their stomachs that they press against the eggs to keep them warm.

Every so often, we also see the parents looking up and calling out to something in the sky over them. Threats to an osprey nest depend on where it is located. A land nest is vulnerable to raccoons, skunks and foxes, which is why most ospreys that are nesting on land like to be very high in the air -- like our ospreys on the cam platform. When the osprey nest is high, the main threat will then come from the air.

What could threaten the ospreys and their eggs? Possibly a single male or female osprey that has not found a nest or a mate, and is looking for a bit of trouble. In addition, sometimes bald eagles will fly too close to an osprey nest, making the osprey parents aggitated. If the parents left the eggs completely unattended, then crows, ravens, and jays would surely pay the nest a visit. But one of the greatest threats at this stage would be from a Great horned owl -- also called the "winged tiger" (click on the thumbnails below):

According to osprey expert Alan Poole, the nocturnal Great horned owl is one of the only species known to take out an adult osprey sitting on a nest. During Poole's experiences with ospreys he has found dead incubating females that possessed talon marks much like those of a Great horned owl.

Fortunately, these attacks on the adult are rare. It is more likely that the owl would try to take the eggs or the chicks. This same threat would have also applied to the bald eaglets when they were younger -- and that is why we would see the mother eagle keeping watch over the chicks at night on the Eagle Cam.

Great horned owls are found throughout Maryland, and last year after the ospreys had migrated, we were treated to the sight of one on the osprey platform at night.

Despite their formidable reputation and appearance, Great horned owls are beautiful and amazing creatures that perform very useful and important services in our environment. Great horned owls are vital to controlling populations of small and medium-sized mammals, and they actively help farms and local gardens naturally manage their rodent populations without the use of traps or rodenticides. The owls' role in rodent control is also why many people buy those plastic owls from the garden store and place them on their property, because just the threat of an owl is sometimes useful in keeping away the rodents.

In Maryland forests, Great horned owls mostly take rabbits, but also snakes, mice, skunks, ground squirrels, Norway rats, wood rats, and muskrats. Sometimes their diet will also include toads, lizards, frogs, turtles, coots, geese, herons, and avian chicks. Biologists report that despite this varied diet, nine out of ten times the owl's prey will be a mammal.

The Xcel Energy website has an active Great Horned Owl Cam that is interesting to watch. At this time, they also have several photos posted that show the hatching of this season's two chicks -- or owlets.

You can learn more about Great horned owls by reading their informative Life of a Great Horned Owl fact sheet (a PDF file).

Until next time,
Lisa - webmaster
(contact)

Fourth Egg

First, I wanted to mention a new feature on our website. Over the past year, a number of our cam watchers had expressed an interest in making an online donation to the Friends of Blackwater using their credit cards. We have now added a PayPal donation button to our Support page for those who would like to donate electronically. We thank our supporters who help make our projects -- like the raptor cams -- possible. If you have questions about donating, be sure to also check out our Donation Policy page.

Nest Update: As we mentioned on the cam page earlier, we now have four eggs at the nest. We believe the fourth egg was laid on the afternoon of April 20, which was when several cam watchers said they thought they saw it. We then had our ranger confirm that he saw a fourth egg on the TV monitor at the Visitor Center. So we can add the following to our scorecard:

4th egg
Date laid: 4/20
Possible hatch: 5/28

Several cam watchers have asked if four eggs is a good thing. While it is certainly very exciting since we've never had four before at the platform, several of us here at the Refuge would have preferred to have only three eggs.

The likelihood of four chicks surviving and fledging is very small. We have never had even three chicks survive at the platform, let alone four. Unfortunately what will most likely occur is that one or two of the eggs might not hatch, or one or two of the chicks will perish early on.

While our parents seem very capable, and the fish in the region are plentiful, raising four chicks to fledgling age is a difficult task for even the most skilled adult ospreys. So while we hope for the best, we want to prepare our cam watchers for the possibility that some of the chicks might not make it, assuming all the eggs hatch.

As we've seen in our many years with the cams, a raptor chick must be tough in order to survive in the nest. But this is Nature's way of weeding out the weak and ensuring that the ones most likely to survive will get fed and nurtured. In the end, it is only the strongest chicks that can prosper in the larger world with all the challenges that await them -- both natural and man-made. We wish the family the best of luck with their four new eggs, and we hope for the best.

On a final note, I wanted to share a couple beautiful osprey images sent to us by Randy Loftus of the U.S. Fish and Wildlife Service. Click on the thumbnails to see a larger version:

Randy's "Three Osprey Chicks" photo won 2nd prize in the Fall 2005 Chesapeake Bay Foundation's Photo Contest. Randy took the photo while he was out on the water helping to clean hazardous material -- like fishing lines -- from osprey nests. Much thanks to Randy for his work and his photos.

Happy Earth Day everyone!

Lisa - webmaster
(contact)

Eggs Two and Three

Nest Update: Congrats to the proud parents on their three eggs! Four eggs are still possible, but it seems unlikely as we've never had four eggs at the platform. If the fourth did arrive, however, it would be within the next three days. For those keeping score, here is where we stand:

1st egg
Date laid: 4/11
Possible hatch: 5/19

2nd egg
Date laid: 4/14
Possible hatch: 5/22

3rd egg
Date laid: 4/17
Possible hatch: 5/25

The mother osprey laid the first egg in the evening, the second in the afternoon, and the third in the morning. Apparently time of day for laying an osprey egg is variable. :-)

Here's a photo that provides a good look at the coloring on the osprey eggs. You can see how these eggs contrast with the almost pure-white eagle eggs.

Some might wonder why osprey eggs have coloring but the eagle eggs don't. A prime reason might be because of the raptors' different nesting styles. Ospreys prefer to nest out in the open where they can see the sky all around them, and this means their eggs would benefit from some camouflage, such as mottled markings. Eagles, on the other hand, prefer to nest beneath the crown of a tree, with branches providing shelter overhead, so their eggs are not as exposed and are not in need of camouflage.

These nesting styles might also explain why osprey chicks are taught to drop down flat on the nest when the parent sounds an alarm call, while the eaglets do not seem to exhibit this behavior.

A different type of photo I wanted to mention was taken last Friday, when we caught the ospreys watching a U.S. Fish and Wildlife Service tractor going by in the impoundment area behind the platform. Our friendly ranger, Tom Miller, told me that they're breaking up the soil for future planting. Tom said that when they do plant, it will likely be Japanese millet -- a fast-growing grass, which produces a lot of edible seeds, grows well in marsh areas, and is favored by migratory ducks.

And one final photo: This rear-end shot shows how unbelievably close our camera came to being sprayed all-white on Monday, right before the egg arrived. After seeing this close call, we should feel highly fortunate that we can see the nest at all. :-)

Gallery Submissions

As long as the Friends of Blackwater website has had raptor cams, we have also had our online Galleries.

The Galleries serve several important purposes, such as allowing cam watchers to get caught up on the action that they might have missed, and also allowing us to have a long-term record of what happened season to season. This is especially useful considering the fact that we frequently get the same raptor couples back at the cam nests.

If you've never submitted photos to the Gallery, but would like to do so in the future, please read our Instruction page for easy directions on how to submit your photos. You can submit one photo or many -- it's up to you. Just include your name in the email if you'd like to receive credit on the Gallery page.

In the past, I've asked cam watchers to send their photos to the gallery@friendsofblackwater.org address. But I'm now asking our viewers to please use another address from this point forward.

First, I'll explain why we're changing the email address. Previously, when you sent a photo to our "gallery" address, I had it set up so the email would be forwarded to my Google email account. The reason for this is that Google handles photo attachments very well and will even show me a thumbnail of your photo before I open it. Very handy!

But our web host's email server has had difficulty forwarding the many photos I receive for the Galleries. Three times in the past several months, I've had major delays in receiving "gallery" emails, and last week the problem happened again where emails were showing up as much as 4 days after they were sent -- in fact, some are still arriving as I write this. So I'm eliminating our web host as the middle man, and asking that you send your photos straight to my Google email account so I can be sure to get them in a timely manner.

If you forget and send your email to the old address, that's fine -- I'll still get it. But I would prefer that our cam watchers get in the habit of sending all cam photos to the address below from now on:

blackwatercam@gmail.com

Thanks to our cam watchers for their cooperation as we make this change. I'll be repeating this message in our next Eagle Cam Web Log, so everyone gets the news. And thanks to all our cam watchers who take the time to submit their photos. Your actions add much value to our website and to our educational efforts here at the Refuge.

I'm going to hold off updating both the Osprey and Eagle Cam Galleries for a few days until all the late-arriving emails have a chance to come in.

Until next time,
Lisa - webmaster
(contact)

First Egg

Nest Update: We're very excited that on Tuesday April 11, the osprey pair delivered their first egg. The parents are doing a good job of caring for it, and they continue to mate even after the delivery of the first egg.

Osprey eggs have a brownish mottled coloring, so if it looks like there is a crack on the egg, it's often just the egg markings. Also if you see the egg briefly disappear, it's often because the parents covered it with sod once they were no longer sitting on it. The sod keeps the egg warm and hides it from predators, such as crows, Great horned owls, and even eagles.

Ospreys will normally lay two to four eggs, at an interval of one to two days apart, although sometimes three days. Incubation lasts around five or six weeks, and if the eggs are fertile, they will hatch in the order they were laid.

At the cam platform, we've never had more than three eggs laid. In 2004, all three eggs hatched, but the third chick only lasted several days and then sadly perished. In 2005, we had three eggs again, but lost sight of one egg while the other two hatched. We believe the missing chick might have hatched and then died immediately, as its egg disappeared on the day it was scheduled to hatch.

Like the eagles, both osprey parents have a brood patch and both share in the incubation duties, although the mother will incubate the majority of the time (around 70%). Incubation can be a bit sporadic until the second egg arrives, but then the parents will remain on the eggs a good part of the day and night. During the evening, the female will normally do all the incubating.

Osprey eggs, which are about the same size and shape as large hen eggs, have long been admired for their unusual coloring. Noted ornithologist Arthur Cleveland Bent called osprey eggs “the handsomest of all the hawks’ eggs” due to their color variations. Unfortunately egg-collecting played a major role in the population crash of United Kingdom ospreys during the 19th and 20th centuries, and remains a problem even now, as the osprey population is starting to revive.

You can view a close-up of osprey eggs at this Random House web page -- their photos illustrate the color variations on the eggs.

Once the eggs hatch, the chicks will look like the photo to the right, showing two newborn osprey chicks (about one and two days old) from Maurice River, New Jersey. Notice the unhatched egg in the background. The photo was loaned to us by Jane Morton Galetto, the president of Citizens United to Protect the Maurice River and its Tributaries. Be sure to visit her group's website and look at their wonderful online osprey slide shows.

We thank our cam watchers for the photos they've sent in, which help us to record these wonderful moments with our growing osprey family. We'll keep an eye out for one or two more eggs over the next few days.

Until next time,
Lisa - webmaster
(contact)

A New Season

Nest Update: Since our couple looks very organized and could likely lay eggs soon, we thought it would be a good time to start the Osprey Cam Web Log for 2006.

A Brief History of the
Blackwater Osprey Cam

For those who are new to our Osprey Cam, this is our sixth year with the ospreys on the Internet. Altogether we've watched eight chicks hatch and fledge since 2001.

Unlike the bald eagles, the ospreys do not stay at Blackwater Refuge all year. Ospreys are almost exclusively fish eaters, so they migrate south for the winter, since fish are hard to find in cold or frozen water. They leave us in September and return in March. Our ospreys probably winter in Central or South America.

For the first four years that we were on the Internet, we had what appeared to be the same reliable osprey couple at the nest, and last year that couple returned to us and quickly began building up the platform nest for another season. But then suddenly they up and left for another location at the Refuge.

Later we heard that there was another nest that had been taken down and then restored last year, and our couple may have nested there before we built the cam platform. It seemed the couple remembered their old residence and made the move. After they did this, several other osprey couples battled over our cam platform, and the couple that won spent the rest of the season on the cam nest. That pair went on to produce two fledglings, which we named Thunder and Lightning, since the family sat through a lot of turbulent weather last summer.

So this year as we watch the cam, we naturally wonder who is back at the nest -- couple #1 or couple #2. We honestly don't know. We can say that this year's female has a bigger "necklace" -- the brown coloring on a female's chest -- than last year's mother, which was a bird that possessed a very faint necklace. So we may have a different mother, or she may in fact be the original mother that occupied the nest the first four years on the cam.

As for the father, we don't know which male we have this year, but we hope he is an improvement over last year's male. In 2005, we saw our first real chick aggression at the cam nest, and it seemed to stem from the fact that the father was disappearing for most of the day and not delivering enough fish. There are plenty of fish at Blackwater -- the female certainly found them -- so we gathered that our male was either a bit distracted or was a new father that didn't know how to feed a big family.

The Osprey Cam Location

Several cam watchers have asked about the location of the Osprey Cam. The birds are on a tall land platform that we built specifically for them. Behind them is a water impoundment area where the U.S. Fish and Wildlife Service can control the amount of rainwater that collects (2006 has been very dry). In the distance, you can see the Visitor Center building. If you were standing on the platform looking behind the camera, you'd see the Blackwater River -- where our raptors get many of their meals. At ground level, the platform is near a small pond area where herons, ducks and turtles hang out. Sometimes you see the ospreys looking down at them.

Visitors to our Wildlife Drive at the Refuge can drive right by the Osprey Cam platform and see the ospreys, which are just off the road. Fortunately, ospreys are more flexible about nesting near people than bald eagles are, and the ospreys don't seem to mind hikers, cyclists, and cars going by their platform all day. There is a service road that leads to the platform -- we just ask that folks stay off that road so the ospreys don't get spooked. This photo shows what the ospreys look like when they're watching people on the Drive.

If you'd like to see some photos showing how we installed the cam, visit our Installation page. The platform is very high, and we have to use a bucket truck to get to it. Although the ospreys are more flexible about human visitors, we have to rent the bucket truck from a local company before we can go up, so acquiring it is a big deal and we usually reserve that for emergencies with the cam equipment.

If you have more questions about the Osprey Cam, you might want to read our Osprey Cam Q&A page.

Nesting Action

If you've been watching the action at the nest or looking at our Gallery lately, you've undoubtedly noticed a lot of mating maneuvers. Osprey biologists report that couples might mate 60-160 times during a nesting season. Obviously not all of them are successful, since ospreys lay an average of 2-3 eggs in a nest.

Beyond prodigious mating, the osprey couple seems to be bonding nicely in other ways as well. They've both contributed to the nest building, and the male has been dropping off fish for the female to eat -- a ritual that assures her that he will be a good provider. On Thursday morning he dropped off a fish for her, and then proceeded to do a little nest maintenance himself as he used his chest to mold the nest cup. As for the female, we've occasionally seen her roosting at the platform at night, while the male roosts in a nearby tree. All these signs seem to point to a couple that will likely lay eggs in the near future.

And a final note about our setup: Some cam watchers have probably seen the tape flapping across the lens -- at night it looks rather ghostly. The tape was placed there last season to secure the cam, but it has now worked itself loose. We had planned to remove it before the ospreys arrived, but our cam technician hurt his ankle and had to forgo a trip up to the platform. The tape only appears when the wind is right but then it vanishes. If it doesn't rip off, then we'll remove it the next time we make a maintenance visit to the nest.

We thank you for joining us for another year of the ospreys. The fish hawks have their own unique habits and personalities, and always provide lots of entertaining cam watching for our website visitors. Hopefully they will deliver a chick or two for us to share with you this nesting season.

Until next time,
Lisa - webmaster
(contact)