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Murre ManiacsCommon
Murre Restoration Project:
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| June 2008 | ||
| May 2008 | ||
| April 2008 | ||
| June 2007 | ||
| May 2007 | ||
| April 2007 |
The Murre Maniac
The Common Murre Project Update April 2007
Breeding Season Begins Again
Old Gray with mate on April 22, 2007, USFWS Photo
This month common murres have been seen every day on Devil’s Slide Rock reestablishing nesting territories and looking for mates. We had a high count of 740 murres on April 28th. Our first two murre eggs were seen on Devil’s Slide Rock on April 30th.
Brandt’s cormorants have been busy setting up nests and laying eggs on Devil’s Slide Rock this month. We now have 82 cormorant nests that we are monitoring on the rock, with many more birds still collecting nest material and looking for mates. One of our favorite cormorants, Old Gray, has returned to the island and has been seen with a mate and a little bit of nest material. Old Gray was banded in 1985 on the Farallon Islands with a metal band #02486 on his left leg and a plastic gray band on his right leg; he is 22 years old! We are all hoping his nesting attempts this year will be successful .
So far 41 Brandt’s cormorant nests on Devil’s Slide Rock have eggs. Looking for eggs requires a lot of patience since we have to wait for the incubating bird to move. Sometimes we can see a flash of white from one of the eggs as the bird moves around on the nest, but often we have to wait for the mates to switch (cormorants take turns incubating their eggs) in order to count all the eggs in the nest. Because Devil’s Slide Rock is about 300 meters off shore, we use the video cameras that are installed on the rock and telescopes to observe the birds.
Biologist Lisa Eigner looks for Brandt’s Cormorant eggs on Devil’s Slide Rock. USFWS Photo.
April 2007 Colony Counts of Devil’s Slide Rock
Date |
#Murres |
Date |
#Murres |
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April 4 |
490 |
April 22 |
594 |
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April 12 |
554 |
April 24 |
487 |
|
April 16 |
293 |
April 26 |
329 |
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April 18 |
565 |
April 28 |
740 |
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April 20 |
457 |
April 30 |
605 |
*Compiled by Sandra Rhoades
The Murre Maniac
The Common Murre Project Update May 2007
Murre Eggs!
The common murres on Devil’s Slide Rock have been busy laying eggs and are now sitting carefully and still while they incubate them. Murres do not build nests; they lay their eggs right on the bare rock. In fact most murres will lay their egg in the same spot on the rock each year. Murre eggs have a special shape, narrow and pointed at one end and wide at the other. This pear shape causes the egg to roll in a circle and helps prevent eggs from rolling off the rock. Murre eggs are unique and come in a variety of colors with black or brown spots. This helps to camouflage the egg and protect it from predators that fly over the colony. On Devil’s Slide Rock, we have seen a range of shades from white to pale blue to mint green and bright turquoise. All the eggs have black splotches and the pattern is different on each egg, which may help the murres recognize their own eggs. There have been 220 eggs laid on Devil’s Slide Rock so far this season! We expect to see murre chicks by the first week of June.
Four different murre eggs on Devil’s Slide Rock. USFWS Photo
Brandt’s Cormorant chicks are hatching on the rock. We have counted over 45 nests with newly hatched chicks! Brandt’s Cormorant chicks are very small and helpless when they are first born. At first, these chicks do not have any feathers at all and they must be guarded very carefully from the weather by their parents. After two weeks the chicks grow in down feathers, which helps to keep them warm.
May 2007 Colony Counts of Devil’s Slide Rock
Date |
# Murres |
Date |
# Murres |
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May 2 |
634 |
May 16 |
514 |
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May 4 |
596 |
May 18 |
419 |
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May 6 |
428 |
May 20 |
302 |
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May 8 |
360 |
May 22 |
472 |
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May 10 |
585 |
May 24 |
560 |
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May 12 |
284 |
May 28 |
544 |
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May 14 |
452 |
May 30 |
485 |
*Compiled by Lisa Eigner
The Murre Maniac
The Common Murre Project Update June 2007
Murre Chicks!
June is an exciting month on Devil’s Slide Rock. Those white, blue and green common murre eggs are hatching! The first sign that a chick is going to hatch is a pipping egg. This looks like a small hole in the egg where the chick has begun to break through the eggshell. The chicks have a special adaptation called an egg tooth, which is on the tip of the beak. This sharp egg tooth helps the chick break and tear the eggshell. Once the chick hatches, the parents take turns to find fish and feed it. They bring in young salmon, anchovies, and sometimes squid. Using the video camera, biologists record prey items common murre adults bring for their chicks. With lots to eat, these chicks are growing fast! There are currently over 160 chicks on Devil’s Slide Rock, and approximately 460 adult murres attending daily. Common murre chicks stay on the rock approximately 23-24 days before they jump off from the rock into the sea.
The mainland colony has been a bustling little colony with around 80 Common Murres attending daily. The first murre chicks were seen on the first week of June. There are about 20 chicks on the mainland, and two of them have fledged.
June 2007 Colony Counts of Devil’s Slide Rock |
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|---|---|---|---|---|
Date |
# Murres |
Date |
#Murres |
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Jun 1 |
495 |
Jun 15 |
565 |
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Jun 3 |
426 |
Jun 17 |
514 |
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Jun 5 |
502 |
Jun 19 |
501 |
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Jun 7 |
365 |
Jun 21 |
390 |
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Jun 9 |
341 |
Jun 23 |
394 |
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Jun 11 |
389 |
Jun 25 |
437 |
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Jun 13 |
208 |
Jun 27 |
505 |
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*Compiled by Deasy Lontoh
The Murre Maniac
The Common Murre Project Update July 2007
USFWS Photo
This has been a busy month on Devil’s Slide Rock. Most of the Brandt’s cormorant and common murre chicks have fledged. Cormorant chicks continue to run all over the rock so that we can no longer tell who came from which nest, but some have already left the rock and many of these fledglings can be seen roosting down by the water’s edge.
Most of the murre chicks have also left the rock. When they are ready to fledge, at about 22 days old, they go to the edge of the rock with their parents and make the 75 foot jump off the rock and down into the ocean below. There the chick will stay with its father until it is ready to be off on its own (about 1 to 2 months). Chicks won’t return to the rock until they are ready to breed, somewhere between 4 and 8 years old. Most chicks make this jump in the evening just as the sun is setting, but we watched a few take the plunge during the middle of the day.
Fledging
After being fed for about 22 days, a little murre is ready to change his ways. Instead of continuing his life on land, this fledgling is ready to leave the island. Slowly and carefully he begins to edge over towards the ledge. He hears his dad in the water call and Mom encourages him not to stall. But because he cannot yet fly, he must find another way to try. Finally, he takes one big jump and plummets into the water. Kerplump! Once in the water he’ll stay with Dad for a month or two- he’ll be very glad. He’ll learn how to swim and dive and to catch fish while they’re still alive. He won’t return to Devil’s Slide again until he becomes an adult, and then he’ll walk around and find a mate. They’ll lay an egg and incubate.
July 2007 Colony Counts of Devil’s Slide Rock |
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|---|---|---|---|---|
Date |
# Murres |
Date |
#Murres |
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July 2 |
454 |
July 18 |
225 |
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July 4 |
546 |
July 20 |
418 |
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July 6 |
597 |
July 22 |
250 |
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July 8 |
587 |
July 25 |
320 |
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July 10 |
549 |
July 27 |
334 |
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July 12 |
492 |
July 29 |
126 |
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July 16 |
400 |
July 31 |
156 |
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Compiled Sandy Rhoades
The Murre Maniac
The Common Murre Project Update April 2008
A New Season!
The month of April has kicked-off another breeding season for the seabirds that colonize Devil’s Slide Rock and the Devil’s Slide Mainland. The beginning of the month was chaotic for the Common Murres as they defended territory and shuffled around the rock. Now that the end of the month has arrived, most of the Murres have paired up with a mate and stayed on their territories most of the day. Within the three monitored plots on Devil’s Slide Rock, we have spotted approximately 192 breeding pairs. The first egg of the season was seen on April 29 th on Devil’s Slide Rock, but we are yet to see one on the mainland. As far as the numbers of Murres are concerned, a high count of 785 birds was seen on Devil’s Slide Rock, while 215 birds were counted on the Devil’s Slide Mainland.
Common Murres on Devil’s Slide Mainland
USFWS Photo
The Brandt’s Cormorants have also been busy setting up territories, attracting mates, and gathering nesting materials. Although the Cormorants were off to a slow start earlier in the month, they have picked up the pace and there are at least 68 territories on the mainland, and 28 on Devil’s Slide Rock. We have yet to see any Brandt’s eggs, but we are patiently waiting and monitoring!
The Devil’s slide mainland is hosting a variety of other bird’s nests. There are eight Pelagic Cormorant nests, one of which has 2-3 eggs. There is also a pair of Peregrine Falcons, Great Horned Owls, and Common Ravens nesting nearby. We are excited to see how all these species will interact as the breeding season of the Common Murre begins!
| April 2008 Colony Counts of Devil’s Slide Rock |
|
Date |
# Murres |
April 22 |
785 |
April 24 |
660 |
April 26 |
558 |
April 29 |
650 |
* Compiled by Erica Donnelly
The Murre Maniac
The Common Murre Project Update May 2008
Peak Egg-laying Period!
During the month of May, the Common Murres residing on Devil’s Slide Rock and on the Mainland have been busy laying eggs! Common Murres lay one relatively large egg on their territory. Once the egg is laid, one of the pair always attends the territory to incubate the egg. When a bird is in incubating position, its body looks rounded and its back is arched. The wings are often relaxed and touching the ground to surround or protect the egg. Hours later, the mate that has been out-to-sea returns to the site to take its turn at incubating the egg. The pair switch spots with care so that the egg does not roll to a different site or off the rock! If an egg rolled off site, a murre will carefully roll it back to the appropriate spot using its bill and body. Murres will continue incubating their egg for 30 days at which time, a chick will emerge!
By the end of the month, we were monitoring 200 sites on DSR, 29 of which had retained their eggs. On the Mainland, there were 109 sites and 10 eggs. The eggs we have seen varied in color, from a light white, blue or green to an intense teal or turquoise! The eggs also have a variety of patterns from speckled or swirled with black markings to plain ones.
Common Murre on Nest USFWS Photo |
We have yet to see any Brandt’s Cormorant chicks, but there are quite a few nests with eggs on the Mainland.
We are expecting to see their chicks by the second week of June!
May 2008 Colony Counts of Devil’s Slide Rock |
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Date |
# Murres |
Date |
# Murres |
|
May 1 |
555 |
May 15 |
662 |
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May 3 |
798 |
May 17 |
427 |
|
May 5 |
796 |
May 19 |
510 |
|
May 7 |
603 |
May 21 |
267 |
|
May 9 |
735 |
May 23 |
231 |
|
May 11 |
961 |
May 27 |
427 |
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May 13 |
522 |
May 31 |
647 |
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* Compiled by Erica Donnelly
The Murre Maniac
The Common Murre Project Update – June 2008
Growing up!
June is an eventful month for Devil’s Slide Rock. 300 to 600 murres attend the rock daily. Egg-laying has continued with over sixty eggs laid this month. In late June, eggs started to hatch. The first chick was seen on 22 June. Currently, there are 25 chicks on the rock, ranging from one to nine days old.
These young chicks must grow up quickly because at 23-24 days old, they will fledge. So, they have to eat a lot! One adult murre usually stays with the chick, while another forages for food. The foraging adult will then return with a prey item, usually dangling from its bill, to feed the chick. Devil’s Slide Rock murre chicks primarily eat fish, especially anchovies. Chicks are fed a single fish two to five times daily. The chick feeding rate can vary with the size of the prey, caloric value, availability and chick age. 1-2 days-old chicks are fed two fish per day while 9-10 days-old chicks are fed 4-5 fish on average. When fish are difficult to find, the foraging parent have to spend more time hunting thus lowering daily feeding rate.
While murre chicks just started to hatch, other seabird chicks on Devil’s Slide Mainland have been growing for sometime. Many Brandt’s and Pelagic Cormorant chicks have started to grow their contour feathers, replacing their down feathers. Some of them are very active and close to fledging. Unlike murres, cormorant chicks do not eat their fish whole. They eat partially-digested fish that their parents regurgitate in small morsels. Western Gull chicks started to hatch mid-month. Their bodies are still mostly covered in down but few have started to grow contour feathers on their wings.
June 2008 Murre Counts on Devil’s Slide Rock
Date |
# Murres |
Date |
#Murres |
6/2 |
684 |
6/18 |
415 |
6/4 |
588 |
6/20 |
339 |
6/6 |
488 |
6/22 |
564 |
6/8 |
372 |
6/24 |
424 |
6/10 |
343 |
6/26 |
407 |
6/12 |
399 |
6/28 |
377 |
6/14 |
479 |
6/30 |
484 |
6/16 |
593 |
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*Compiled by Deasy Lontoh
