Let’s review the Loon Cam nesting results so far.
On Cam #1, the loons lost one egg due to some frantic nest building in response to major rainfall and water level rise. Then we celebrated the hatching of one chick, only to watch an eagle carry it away before it had a chance to leave the nest. 0 for 2.
So far on Cam #2, we’ve witnessed one egg get accidentally crushed and then disposed by the loons. The crushing appears to have happened during a violent thunderstorm. So we’re pinning all our hopes on the one remaining egg in the Cam #2 nest. So, a pretty pitiful year, huh? Well, maybe we shouldn’t jump to conclusions… yet. Lets compare the productivity of these two nests this year to the average statewide loon productivity and see what we get.
Nest initiation: Statewide, about 70% of territorial pairs actually nest; on the Loon Cam we have 100% (2 for 2).
Nesting success: Statewide, it averages around one chick hatched per nesting pair. On the Loon Cam it’s going to be either 0.5 or one chick hatched per pair.
Chicks surviving per territorial pair: Statewide average is about 0.5. The Loon Cam average will be 0.5 if the remaining egg hatches and the chick survives to the end of the season.
So, pinning our hopes on the remaining egg, this would be about as close to a “typical” season as two random pairs could get. We’ve just been spoiled over the past few years by watching two excellent nesting pairs.
Here’s hoping for a “typical year”.
At 3:56 pm yesterday, a full ten hours after nest abandonment, Dad returned and continued incubation. Mom took over a couple hours later and we’ve had constant incubation since then. So everything is copacetic, right?
Maybe. Ten hours is a long time for an egg to go without incubation. A lot depends on the weather during the time the egg was exposed. The good news is the temperatures were mild (afternoon maximum of low 80s) and there was very little direct sunlight before mid-afternoon (conditions ranged from fog to overcast to cloudy). So it’s unlikely the egg heated up to more than 100 degrees F. Normal incubation temperature is estimated to be in the mid to high 90s. However, the morning temperatures during the fog and overcast ranged from low to mid 60s for the first four hours of exposure. Minimum temperature and exposure time tolerances are not definitively known for loon eggs. We can’t be certain that the egg is still viable but we also think there could be a good chance that the egg could still hatch.
Some might argue that the first egg in a two egg clutch is sporadically incubated, sometimes left unattended as much as this egg was, and it will still hatch. But that’s not a fair comparison. A freshly laid egg has a fertilized embryo that can remain in suspended animation. An egg midway through the incubation process has numerous metabolic functions occurring that can be temporarily slowed down. But if metabolism stops, the the egg will be damaged.
Folks have asked if going 10 hours without an egg turn could hurt viability. Again, we don’t have any definitive data for loons but other species that have been studied show that egg turning twice a day is adequate for proper development. This shouldn’t be an issue.
Like all else in nest sitting, all we can do is wait and see. If the egg hatches, we’ll have an interesting data point for our understanding of incubation. If the egg doesn’t hatch, all we can do is scratch our heads and wonder.
“May You Live in Interesting Times”
It seems that something has cursed the Cam 1 pair with this left-handed blessing. In previous years we’ve witnessed hail the size of golf balls pelting the nest, an AWOL Mom during hatch, lost eggs – both kicked into the water and buried in the nest – and an eagle flying off with a chick. It’s truly amazing that this pair has managed to meet or exceed the statewide productivity (chicks surviving) rate during this time.
This year is no exception. Lake residents have reported that there have been “visiting” loons on the lake for quite a while. Any extra adult loons are a threat to the resident pair and particularly a threat to any recently hatched chicks. Basically, there’s a territorial war going on.
Somehow the pair has managed to have a successful nest while dealing with the intruding loons. The second chick hatched yesterday morning. Under normal circumstances, the family would leave the nest after the new chick had dried off and then become accustomed to swimming, which only takes a few hours. The brooding area, which is where the pair would take the chicks because it has plenty of bite-sized chick food, is on another part of the lake and near where the intruding loons are lurking. In effect, the family is under siege and cut off from essential food supplies.
During and after the hatch, Mom and Dad have each gone off to battle with the intruders while the other tends to the chicks. There was a brief time last evening when it appeared that the pair had vanquished the enemies. A lake resident reported seeing a loon flying off and leaving the lake and Mom, who was on the battle lines at that time, returned to the nest area and there was a raucous celebration of tremolos. But they still wouldn’t leave the nest area. Mom took both of the chicks and returned to the nest, where the three of them spent the night. The loons obviously still perceived a threat. We assume Dad resumed patrol duty.
This morning things still haven’t changed. A lake resident reports that there is still at least one intruding loon on the lake and the chicks are confined to the nest area, in the company of one adult. We’ll keep watching and reporting. There will be another post shortly that discusses an encounter that deserves its own blog. Stay tuned!
A Busy Day!
Two Loon Cams going and major events happening at both of them.
On Loon Cam 1 the pip was first observed yesterday at 4:16 pm and this morning the chick hatched around 4:00 am. It’s a feisty one and it escaped Mom’s sheltering wing and made a solo voyage. Mom called for Dad to come back to the nest but a local lake resident reported that Dad was busy dealing with a visiting loon. What terrible timing! Mom managed to coral Junior and entice the chick back into the nest. It remains to be seen what the outcome will be concerning the extra loon on the lake. We’re hoping Dad can convince the visitor to leave.
On Cam 2 the second egg was laid around 8 am. (The first egg showed up Thursday afternoon, before the cam was set up.) So this pair has started its (hopefully) routine incubation duties with the first hatch expected around July 8 or 9.
So the action for the next day or two should be on Cam 1, where there is still an egg that is expected to hatch sometime tomorrow, and a new chick to entertain us while we’re waiting for the second hatch.
The Pip Watch Begins
It’s getting close to hatch time, which we would expect to be most likely Sunday or Monday. Hatching is a relatively long process. It can take up to 20 hours for the chick to completely break apart the shell. The first clear visual sign of an imminent hatch is the pip, a tiny hole at the blunt end of the egg. A loon sitting on the nest can be aware of an impending hatch before the pip because it can sense movement in the egg, which may cause the loon to be more attentive to the egg, frequently shifting its weight or rising up to inspect the egg. It’s always fun to watch for these signs and be the first to see the pip. By tomorrow (Saturday), it will be prime time to be on pip watch. (Unless it happens sooner. Mom is acting kinda twitchy this morning)