Skinks in North America


This video from the USA says about itself:

Four-Lined Skink Found In Bush Alongside Brownsville Texas

11 February 2014

Plestiodon tetragrammus. The four-lined skink is a species of lizard, which is endemic to North America. It feeds on insects and spiders. It is a medium-sized member of the Plestiodon skinks. It ranges through Central and southern Texas, south into Mexico, north to south-central Arizona and extreme southwestern New Mexico.

From eNature Blog in the USA:

Blue Streak Special— Ever See A Skink?

Thursday, July 10, 2014 by eNature

There’s a rustling in the leaves. You look to see what made the sound, and bam—a blue streak vanishes into the duff. Was it a snake? A lizard? Was that intense cobalt color even real?

Yes, it was real. The creature responsible for the streak was a lizard called a skink. Now’s the time when the newborns hatch, and the intense blue tails of the juveniles are as bright as neon signs.

There are fifteen species of skinks in North America, a small percentage of the 1,200-plus species found worldwide (it’s the largest family of lizards). Most species keep their blue tails for the first two years of life; the tails of adults fade to gray or brown. As for why the young skink needs such a gaudy appendage, the standard textbook answer is that predators like birds and mammals will grab first at the bright tail. Because the tail easily detaches, the lizard escapes—tailless, yes, but at least still alive.

If this strategy is so advantageous, though, why don’t adult skinks have blue tails? One possible explanation is that young skinks tend to spend more time above ground where they’re subject to more predators. When they become adults, skinks establish territories inside rotting logs or under rocks and spend little time moving from place to place. (To tell the difference between a mature male and a mature female, look for the orange highlights on the male’s head.)

Mating takes place in the spring. Then, in late spring, the adult females retreat to burrows or other sheltered recesses, often deep in the ground, where they lay eggs and remain with them until hatching. A female may keep its eggs moist by licking them or otherwise moistening them or it may simply guard the clutch of two to six eggs. When the eggs hatch, adult females and their brightly colored newborns come to the surface to feed on insects and spiders for the summer. The first chill of autumn sends them underground, where they wait until the first warm days of spring beckon them back to the surface.

Have you come across skinks or other colorful amphibians? We always enjoy your stories!

Skinks are not amphibians, of course, but reptiles.

‘Supermoon’ in North America tonight


This video is called SUPERMOON TONIGHT July 12, 2014 – The 2014 Supermoon Summer!

From eNature Blog in the USA:

Don’t Miss Tonight’s Supermoon!

Posted on Saturday, July 12, 2014 by eNature

The moon that rises tonight (Saturday) is what has come to be called a “supermoon” — only hours from being perfectly full and hours from one of the year’s closest approaches to Earth.

This combination makes the moon appear bigger and somewhat brighter than usual, even for a full moon. And because the moon always looks larger as it rises, moonrise Saturday night may show off a moon that appears about as big, bright and round as the moon can get.

As the moon rises in the southeast at Saturday evening (at 8:30 or so on the East Coast) it will move west across the dark heavens through the night and early morning before setting in the southwest on Sunday morning.

Astronomers caution that without special equipment it’s difficult for the average skywatcher to assess the moon’s brightness or size. But a supermoon last year was reported to be about 15 percent larger and 30 percent brighter than the year’s run-of-the-mill full moons, and many people may consider themselves capable of spotting a 30 percent boost in brightness.

Of course, the brightness of the moon, as seen from earth, will depend, in part, on the sky’s clarity and the amount of cloud cover. If clouds do intervene, the next supermoon is not far off. There will be one in August and another in September.

More on the supermoon at Earthsky.com.

American goldfinches, why do they nest late?


This video is about American goldfinches singing.

From eNature blog in the USA:

What Makes Goldfinches Wait Until July To Nest?

Posted on Tuesday, June 17, 2014 by eNature

By July, most songbirds are in the final stages of raising their young, but not the American Goldfinches.

These appealing, colorful birds are just getting started.

Notoriously late nesters, goldfinches have been waiting for the thistles to bloom. When this happens in July, it signals the goldfinches that they can start building their nests which are made primarily of the silver fibers and down of thistle blooms. Generally, the nest is built in the fork of a horizontal tree limb, 4 to 14 feet above the ground.

The female builds a durable, neat cup of thistle and cattail fibers, so dense that it will hold water. In it she lays 4 to 6 pale blue to white eggs and then she incubates them for 12 to 14 days, until they hatch. The attentive male often feeds his mate while she sits on the nest.

By the time the eggs hatch, the thistle has gone to seed, which is perfect timing for feeding young goldfinches. The parents nourish this chicks by consuming the thistle seed themselves, and then regurgitating the partially digested, milklike cereal into the mouths of their nestlings. This is as close as birds come to mammals that feed their young milk from mammary glands.

Baby goldfinches are fully feathered and out of the nest 10 to 16 days later. Almost immediately, they join their parents at bird feeders across America. That’s when many people suddenly notice so many goldfinches as the summer progesses.

Have you seen nesting goldfinches yet? Or young preparing to fledge?

Let us know by sharing your stories below.

Learn more about all three species of Goldfinch found in the US here.

North American birds in art


The Cornell Lab of Ornithology in the USA writes about this video:

A Supersize Mural Honors Peterson’s Famous Silhouettes

Many bird watchers remember the neat black silhouettes in the endpapers of the classic Peterson’s field guides—an eloquent reminder about the value of size, shape, and posture. Now, the Cornell Lab’s visitor center echoes those pages in a magnificent 40-foot-high mural painted by James Prosek. Featuring 170 birds, the mural celebrates biodiversity and challenges viewers to identify both the familiar and the unusual. Watch this video showing the mural coming to life.

North American bird songs learning game


This video from the USA says about itself:

Bird Song Hero: The song learning game for everyone

27 May 2014

For the full challenge, including the Bird Song Hero Ultimate round and free bird song downloads, visit here.

Train your brain to recognize and remember bird songs with the Bird Song Hero matching game. In this five-question video quiz you’ll listen closely to featured songs and match each with the correct sound visualization. Bird Song Hero is a fun way to practice the key skills you need to ID all the bird songs you’re curious about. Brought to you by the All About Bird Biology team at the Cornell Lab of Ornithology. You can find more interactives, quizzes, and videos to help you understand birds on our free educational website.

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How to see North American songbirds migrating


This video from the USA is called Studying Songbird Migration Patterns in the Gulf of Maine.

From Audubon magazine in the USA:

Migrating Songbirds Are All Around You. Here’s How to Spot Them

Forget traveling to a migration hotspot. Right now it’s easy to see small migratory songbirds no matter where you live.
By Kenn Kaufman

Published: 05/01/2014

I can’t help it. At this time of year, I’m obsessed with bird migration. I talk about it with everyone—even complete strangers. Often I hear responses like this: “Well, I’d like to see migrating birds sometime. But I don’t live on a flyway.”

Here’s the good news: We all live on a flyway. It’s true that some birds, such as geese and cranes, follow fairly narrow corridors of travel, and shorebirds will gather only at certain spots. But right now, in early May, hundreds of millions of small songbirds are migrating north, and they pass over every square mile of land and water in the temperate regions of North America. In fact, during their travels, a few of them will stop in just about every tree on this continent. So no matter where you are, you have a chance to see some migrating songbirds.

The nature of their travel

The stars of the show right now are small birds that travel large distances: songbirds that spend the winter in the tropics, coming north to spend the summer in the United States and Canada. These birds—dozens of species of warblers, thrushes, vireos, orioles, flycatchers, tanagers, grosbeaks, and more—migrate mostly at night. They take off just after dark, fly through the night, and land near dawn, if they’re over land at that point (if they’re over water, of course, they keep going). They may cover 200 miles or more during a night flight, and when they come down, they need to rest and feed and build up their strength for the next flight.

These birds have amazing navigational powers. A blackburnian warbler, for example, might fly from Maine to Ecuador in the fall, coming back in spring to the very same tree in Maine where it sang the year before. But during their night flights they are subject to wind and weather, so in the morning they might come down practically anywhere. If they still have energy left, they may fly several miles after sunrise, looking for a choice patch of woods or marsh or meadow. But eventually, each bird will settle for whatever spot it can find, and that spot will have to serve as its stopover habitat.

Where to look for migrants

The short answer is that you can look for them almost anywhere. Most of the migratory songbirds live in trees and shrubs, so they’ll settle for even one tree or one shrub, at least temporarily, if they have no other choice. (I once saw an ovenbird and two American redstarts in the shrubbery of a small planter at a bank building in downtown Philadelphia.) Small city parks often host a fine assortment of migratory songbirds; the surrounding square miles of concrete serve to concentrate the birds, as the tired migrants gravitate toward the small patches of green. Isolated trees in city backyards or hotel courtyards may act as stopover habitat for small birds that are just passing through.

Very large patches of habitat, such as large parks or forest areas, can be better for the birds but more challenging for the birders, as the migrants become harder to find in those surroundings. Songbirds in stopover habitat often gather in mixed flocks, so if you’re not seeing any birds, keep moving until you find a migrant—then look around to see if it has company.

When to look for migrants

Because these birds travel at night, early morning is the time when they’re most likely to be seen in marginal habitats. By later in the day, they may have moved on to look for another spot with taller trees or thicker thickets. If you have a backyard or a nearby park with only a few trees, try to check them first thing in the morning to see if any new visitors have arrived overnight.

Some nights produce much heavier bird traffic than others. Watch the weather to look for good flight nights. The ideal night in spring will be when areas just to the south of you have clear skies, warm temperatures, and steady winds out of the south. If storms move in during the latter part of the night, the rain will cause birds to come down wherever they happen to be at that point. A damp morning after overnight showers can produce a bonanza of new migrants in your local trees.

Be alert to the possibilities

Most people don’t see migrant birds because they don’t look for them. You can increase your chances simply by being aware of the possibilities. Get a bird checklist from your local Audubon chapter, borrow a basic field guide from the library, and try to get a general idea of the groups of migratory birds.

And above all, just take a second look at any bird that you notice. That brown bird under the hedge might not be one of the local city sparrows—it might be a Swainson’s thrush, just arrived from Panama. That yellowish bird in the tree might not be a local goldfinch—it might be a Cape May warbler that has just flown in from Jamaica. At this time of year, migratory songbirds are everywhere, pausing for a moment in practically every tree. Just by paying attention, you may get to make the acquaintance of some amazing world travelers.

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103-year-old orca still swimming


This video is called Amazing Orca Killer Whales In The Wild [Full Nature Wildlife Documentary].

From Wildlife Extra:

An orca called Granny swims into the record books

Just in time for Canada’s Mother’s Day last Sunday an orca named J2 – more commonly known as Granny – arrived in the waters between Point Roberts in Washington State, USA, and East Point on Saturna Island in British Columbia, reports The Province newspaper. This was not unusual as J-Pod – the name researchers have given this group of orcas – would normally be expected in the area. What did excite Captain Simon Pidcock of Ocean EcoVentures in Cowichan Bay was the continuing appearance of Granny because she is believed to be 103 years old. She is the world’s oldest known orca and has lived far in excess of the average lifespan of 60 to 80 years for a wild animal.

There was no doubt the orca was Granny, according to Pidcock. He recognises the senior cetacean by her saddle patch, a distinctive white patch each whale has behind its dorsal fin. “They’re like our fingerprints,” he said.

Granny is also recognisable because of a half-moon-shaped notch on the trailing side of her dorsal fin.

Granny is one of the southern resident group of orcas that inhabit the coastal waters from Haida Gwaii, on the north coast of British Columbia, to Northern California for about eight months of the year. Michael Harris, executive director of Pacific Whale Watch Association, which has members in both the US and Canada, said J-Pod had been spotted off the Russian River in Northern California just over a week before.

“The thing I found really interesting is that she’s in the shape to travel, to make the trek she just did with J-Pod,” said Harris. “That’s 800 miles in not even eight days. It’s amazing.”

She appears healthy because of the lack of a “peanut head,” which Pidcock said is a divot-like depression around the animal’s blow hole which appears when they are malnourished. Her endurance and healthy appearance may come from feasting on recent big chinook salmon runs near the Columbia River.

Granny’s birth date of 1911 is an extrapolation by researchers based on her offspring.

She currently has a great-grandchild travelling in J-Pod. Pidcock said researchers also determine age based on the size of the whales, and Granny’s current bulk can be compared to photographic images taken of her in the late 1930s and early 1940s.

The oldest orcas in captivity are both about 50 years old, according to the Pacific Whale Watch Association, and belong to the northern and southern resident groups that travel through the Pacific Northwest.

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