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Robin Migration Update: April 30, 2002
Today's Report Includes:
- Migration Update: They're Almost All Back!
- Backyard Problems
- More Robin Worries
- Now for the Good News! Robin Hood Returns!
- Growing Babies! Robin Nest Cam Videos: Challenge Question #29
- Julie's Robins: Ready, Set, GO! Challenge Questions #30 and #31
- Discussion of Challenge Questions #18-23
- Discussion of Challenge Questions #24-27
- Window of Vulnerability: Discussion on Challenge Question #28
- Year-end Evaluation: Please Share Your Thoughts!
Migration Update: They're Almost All Back!
Despite the bad weather that has plagued most of the continent this spring, from late, deep snows to tornadoes, robins are just about all done with migration now, and are starting to nest in many places.
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Robins have been seen at just about all the Northern Observation
Posts now, including at Anchorage, Alaska, where the first one was reported on April 11. But between the late
April snowstorms and tornadoes around the continent, robins are having a tough spring! And the robins back at the
Northern Observation Posts are no exception.
On April 19, Bruce Bennett wrote from Whitehorse, Yukon Territory, "It is turning out to be a hard spring
for northern migrants." And on April 23, Ken Moore from Stirling, Alberta wrote,
"Just thought I'd let you know what the robins are facing here in southern Alberta right now. An area extending from the southeastern corner of our province to the Rocky Mountains in the west and extending 100 miles northward a spring snowstorm has left about one foot and upward of wet heavy snow on the entire landscape.
"At 7 am this morning I was out in my backyard beating the heavy snow off the branches of my trees before the evergreens, ash, maples and crabs lost any of their branches. My hedges, cotoneaster and villosa were already flattened or bowed from the weight of the snow. While I was knocking the snow off the various trees there were robins sitting on branches of green ash trees as snow continued to fall. Then I watched as they flew to one of my mountain ash trees looking for berries, then a crab apple tree looking for last fall's apples.
"I put real apples and raisins out for the robins but I know that the robins around the village would have a tough time of it today. I'm writing this at 9:30pm. It had melted somewhat during the day but I still have at least 4 or 5 inches of snow on the level. Only the roads have cleared. Hopefully, the ground will be seen tomorrow although the forecast high is only supposed to be +5C. More snow flurries are predicted over the next few days."
Remember to make YOUR predictions about the first robin seen and the first robin song in the Northern Observation Posts.
Backyard Problems
Tim and Julia wrote to Journey North's robin expert needing advice. "We are located in Cincinnati Ohio. A robin has created a beautiful nest in our flower pot on the deck of our porch. Yesterday she laid her third egg with a pattern of laying an egg a day. It appears that she primarily sits on her eggs at night and periodically visits the nest during the day. We are concerned about the accessibility of her nest. When the eggs hatch, the baby robins will be in danger of cats and other animals. The flower pot where the nest is located is on a seat bench on the deck. Can we move the nest to a safer place? Do you have recommendations on what to do?" A couple of days later they wrote again: "A new problem surfaced. Yesterday she laid her fourth egg. This morning at 8:00 there were still 4 eggs; however this afternoon at noon, there is only one egg in the nest! Is a robin known for moving her eggs to another location? They are nowhere to be found around the yard."
In the same way that humans eat chicken eggs, many animals eat robin eggs. Blue jays and crows are two of the most well-known nest predators, but snakes, chipmunks and squirrels are just as likely to visit robin nests to steal and eat the eggs. Mother robins never move their nest or carry healthy eggs away. The most likely thing that happened is that a nest predator took the eggs.
Could Tim and Julia have prevented the problem by moving the nest? Nope! Even if they'd only moved the nest a few feet away, the place would not be the same spot the female robin chose, and she'd KNOW that humans had discovered the nest site, so she'd abandon the nest. The best thing we can do when we see a robin nest is hope that everything will go okay. If we hear robins making a distress call, we can go out and chase away whoever is bother them, whether it's a cat or a crow, but sadly, once a predator has discovered a robin nest it usually keeps coming back until it gets the eggs or nestlings. Journey North's robin expert Laura Erickson has sometimes kept her dog outside when a robin was nesting in her spruce tree-the dog leaves birds alone, but does chase squirrels, and blue jays and crows are scared of her.
Female robins are very good at building their nest in safe, secret spots, but nevertheless, a great many robin nests are depredated. That is why in most places in the US and southern Canada, robins nest three or even four times a season, and even in the northern parts of their range, robins usually nest at least twice. Even though each pair produces about 8-16 eggs every summer, the robin population does not increase because so many things kill eggs and baby robins. Fortunately, when the eggs are stolen, the mother quickly re-nests, and chances are good that she'll choose a safer spot for her next try!
More Robin Worries
Jennifer and Rowan ask, "I just wondered how long can robin's eggs be left unattended? There are 4 eggs in a nest, in a basket hanging from my back porch. I did see the bird there, but it hasn't been there for about a day now and the weather is quite cool. I live in Guelph, Ontario. If the bird comes back could they still survive, or do they need fairly constant incubation, right from the start?"
Robins lay 4-5 eggs, and first nestings of the season often have 5 eggs. The mother virtually never starts to incubate until she's laid a complete clutch. Cool weather doesn't hurt the eggs as long as they don't actually freeze. The tiny babies won't develop inside the eggs until they are heated, and so by waiting until she has a complete clutch, the mother has a better chance that all the babies will develop together, hatching out close to the same time and growing at the same rate.
Sometimes something happens to the mother, or she's stressed out by seeing a predator near her nest, and abandons it. But usually this early in the season she's simply not started incubating yet. We hope the eggs will hatch into healthy baby robins for you to enjoy!
Now for the Good News! Robin Hood Returns!
Journey North's own Julie Brophy has a treasured friend, Robin Hood, the son of a robin who lived in her backyard four summers in a row. To learn about Robin Hood's father, Buddy, see Waiting for Buddy. Robin Hood hatched out in 1999, and returned in 2000, 2001, and now again in 2002! How does Julie know this robin is the same one each year? She writes, "I recognize him by behavior and physical appearance too:
- We have fed him at specific locations, and when spring comes, he positions himself at those locations, and waits (outside upper balcony outside bedroom and lower deck outside kitchen). For instance, each morning he lands on the upper balcony around 6 a.m. to be fed. Or if he's not present, I call him and he comes to be fed.
- Also, another unique behavior is that when he's really hungry (like after or before a very cold night) he will come search for us by looking in the windows around the house until he finds us.
- As for appearance, he has always been a big, robust robin. His breast is a very dark rust color. And up until last year the distinguishing feature was that he was unscarred. Late last year he presented with a very slight scar on his left breast. And it's there to this day. He's very quiet, unlike his father, Buddy, who would call to us at the feeding locations."
Pay attention to YOUR backyard robins--see if you can tell individuals apart by their appearance and behavior!
Growing Babies! Robin Nest Cam Videos
This week's Upland Hills School Nest Cam video clips show the babies growing, preening, feeding, and pooping! The new feathers on these growing nestlings are making them very cute, and they are obviously learning a lot about the world now.
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As you watch the video clips, notice all these things:
- In the first clip, the father came in with the food. Which parent deals with the baby droppings in this one?
- In the second clip, two of the babies are preening. Do you think it's hard for the third baby to nap while the other two are grooming themselves?
- In the third clip, the father has just fed the babies, and one of the babies poops. What does the father do with the fecal sac? Do the babies notice when he flies away? Do you think that watching him fly makes them think about the days when they, too, will be able to fly?
- In the fourth clip, two of the babies appear to be sound asleep and the other is sitting quietly when suddenly the father flies in and they all pop up. It looks like they pop up a split second before he actually lands on the nest. How do you think they knew he was coming? Adults feed the baby or babies that appear to be the hungriest when they return. Do you think being very fast about this makes it more likely that they will get some food?
- In the fifth clip, it's clear the nest is getting crowded. The baby who is preening is perched on the edge of the nest part of the time. Notice how big his or her feet are! The feet and legs of a robin reach adult size before the rest of the baby does, giving the baby a clumsy appearance. Do you think the big toes help it to preen?
Adult robins are supposed to only eat their babies fecal sacs when the babies are very tiny, but this mother robin is not paying attention to that rule in the first clip! To learn more about how the parents deal with baby bird poop, see our lesson The Scoop on Poop: Disposable Diapers for Birds. Then answer
Challenge Question #29:
"Think of at least three advantages of parent birds eating fecal sacs of very young babies. Why do you think they usually stop eating them after the babies get older?"
(To respond to these questions, please follow
the instructions below.)
Julie's Robins: Ready, Set, GO!!!
Let's peek into the nest from Julie's Robin Nest Photo Study and see what's been happening.
Julie's Robin Nest Photo Study
For a better view, click on each photo!
We're SO Crowded!!
Ready, Set....
GO!!!
Challenge Question #30:
"Why do robins leave their safe nest before they can fly and when there are so many dangers outside the nest?"
Challenge Question #31:
"Will the baby robins return to their nest? Where else might they sleep?"
(To respond to these questions, please follow the instructions below.)
Discussion of Challenge Questions #18-23
Thanks to the students who worked on answers to these questions about last week's Robin Nest Video! We put the discussion here:
Discussion of Challenge Questions #24-27
The answers to these questions about last week's Robin Nest Study are at:
Window of Vulnerability: Discussion of Challenge Question #28
Last time we asked, "Why would a robin keep bashing against a window? What could people do to stop it from happening?"
Robins usually bash against windows because they see their reflection in it and believe there is another robin on their territory. As the real robin gets more and more agitated, so does its reflection, and the more aggressive the real robin gets, the more aggressive its reflection. So the problem keeps escalating.
What to do about it? The best way to deal with the situation is to break the reflection. Fifth grader Joseph at Ferrisburgh Central School writes that, "People could put a screen in front of the window or hang something in the window to scare the bird away." Seventh graders Megan, Erin, Niral, and Jeff from Iselin Middle School suggest putting a "decoration on the window. Such decorations could be tape, screens or suncatchers. These will give clues to the bird that an obstacle is in the way." Other alternatives are to soap the window on the outside or cover the window on the outside with paper or cardboard.
Year-End Evaluation: Please Share Your Thoughts!
Please take a few minutes to share your suggestions and comments in our Year-End Evaluation Form. The information you provide at the end of each year is the single most important tool used to guide our planning.
How to Respond to Today's Challenge Questions:
IMPORTANT: Answer only ONE question in each e-mail message.
1. Address an e-mail message to: jn-challenge-robin@learner.org
2. In the Subject Line of your message write: Challenge Question #29 (OR #30 OR #31).
3. In the body of each message, answer ONE of the questions above.
Please Report the First Robin you SEE, the first robin you HEAR singing, and other interesting robin observations.
Your reports will be incorporated into these Robin Migration Updates.
The Next Robin Migration Update Will be Posted on May 14, 2002.
Copyright 2002 Journey North. All Rights Reserved.
Please send all questions, comments, and suggestions to our feedback form
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