Why birds nest near alligators and hawks


This video from the USA says about itself:

Black-chinned hummingbird nesting

8 June 2015

Tucson Arizona. April 24-June 03

Momma building a nest, incubating eggs, feeding young and babies fly off.

One day I was looking out my skinny slice of a bathroom window and I saw a pine tree that had some busy hummingbird activity. I tried to rig up and video from the bathroom window but the vantage point was not good.

I did not want to intrude or cause stress to the mother so from the ground with a tripod set at the highest setting I used a Canon Vixia video camera, 37x zoom, fixed focus and daylight white balance, sometimes I had to adjust the exposure. Using a 64GB card I set up the camera at dawn and just hit record and walked away. When the card was full in a few hours I transferred to a Mac using Final Cut Pro X and selected the clips. Mostly nothing was happening. When all was done the video timeline was about two hours and then I started to eliminate redundant. At thirteen minutes it is still too long but people who like hummingbirds enjoy every minute.

One early morning I found the nest empty as they had already left. I examined the ground below to see if they had fallen out of the nest but that was not the case.

Out of the corner of my eye I spied some bird movement and there was a baby hummingbird on an oleander branch being nurtured by mom. The other baby bird was not to be seen.

Momma often pecked at the baby on the branch— at the head and body trying to encourage flight. And eventually they were both gone. But during the day and the next day there was much flight amongst the pine tree and oleander. Flight training I assume.

I opted to detach and delete the ambient audio as it is near our pool pump and it was annoying.

From the NestWatch eNewsletter in the USA, May 2016:

The Predator Next Door

You might think that a nesting bird would want to be as far away from a predator as it could get and, generally speaking, that’s true. However, it could be very strategic to nest near a predator that is two or more steps above you in the food chain (i.e., your predators’ predator). In this way, some birds derive protection from larger, more aggressive species that keep generalist predators at bay. This phenomenon is called a protective nesting association. Here are two of our favorite examples of nest-protecting predators:

Alligators and Wading Birds

In the southeastern United States, researchers found that wading birds such as herons, egrets, ibises, storks, and spoonbills appear to seek out alligator-inhabited waters above which they can nest. The alligators keep away (or eat) nest predators such as opossums and raccoons, and they cannot climb trees to rob nests themselves. However, the alligators certainly claim any chicks that fall out of the nests from time to time, making it likely that they are also benefiting from their avian neighbors.

Hawks and Hummingbirds

Black-chinned Hummingbirds nesting in southeastern Arizona were found to cluster their nests around the nests of Northern Goshawks and Cooper’s Hawks. Both species of hawk prey on birds, but would not normally bother with something as small as a hummingbird. Researchers found that hummers that nested within 300 meters of the hawks were much more likely to successfully raise young than those that nested farther away.

At least 92 such associations have been documented so far. It is unclear whether the recipients of the protection actively seek out these “protectors,” or if they are simply recognizing that an area has fewer nest predators. Either way, it can pay off to have a formidable carnivore for a neighbor…as long as you fly under the radar.

Alligators, other wildlife in Florida, USA


This video from the USA says about itself:

Florida‘s Alligator Road – Jane’s Scenic Drive

17 apr. 2016

Unique Florida Eco-Tourism experience – Jane’s Scenic Drive in Fakahatchee Strand State Park. This mini-documentary takes a 22 mile drive through the primordial Florida swamp. Exotic plants, birds and wildlife. More information here and here.

Dwarf crocodile saved in Congo


This BBC video from Britain says about itself:

Baby Dwarf Crocodile Hatches in Maddie’s hands! – Earth Unplugged

31 December 2013

Maddie witnesses the birth of two beautiful West African Dwarf Crocodiles and helps them out of their egg shells.

From the Wildlife Conservation Society:

Jaws of Life

February 9, 2016

This dwarf crocodile was rescued from the back of a motorbike by a team of eco-guards at a checkpoint outside Nouabale-Ndoki National Park in the Republic of Congo. It had been bound and stuffed in an empty flour sack.

Dwarf crocodiles are partially protected under Congolese law, meaning special permits are required to hunt them, and hunting is restricted to certain areas and times.

The fisherman who caught this crocodile didn’t have a permit, so the crocodile was rescued.

The guards looked after it for several days until the next patrol was headed north. Then they carried the little crocodile upstream, deeper into the dense forest, and released it well beyond the fishing zone.

In general, crocodile meat is highly sought-after in this part of the world. As road networks expand in the north of the country, logging towns are springing up further into the forest. Their residents are increasingly reliant on bushmeat as a source of food.

Currently, two of the three local species of crocodile, the Nile crocodile and the slender snouted crocodile, are completely protected in the Congo. Little is known about the impact hunting is having on the other—the dwarf crocodile. Given its prevalence on the bushmeat market, its numbers may be falling.

To help, several checkpoints have been set up on logging roads surrounding the national park to deal with the expanding threats to wildlife.

Diver meets big crocodile, video


This video says about itself:

Diver Has Lucky Escape From Crocodile – Super Giant Animals – BBC

5 February 2016

The team follow a crocodile slide into the water to find out where it goes but when they come face to face with it how will they cope?

This was a Nile crocodile in the Okavango delta in Botswana.

Missing link dinosaur nests-bird nests discovery


This video from Canada says about itself:

First feathered dinosaur from North America introduced by Darla Zelenitsky

26 October 2012

Canadian researchers discover fossils of first feathered dinosaurs from North America.

From Science magazine:

Missing link between dinosaur nests and bird nests

By Sid Perkins

25 November 2015 2:00 pm

The links between dinosaurs and birds keep getting stronger: skeletal structures, feathers—and now nests. Whereas some dinosaurs buried their eggs crocodile-style, a new analysis suggests that other dinosaurs built open nests on the ground, foreshadowing the nests of birds.

Interpreting the fossil record is always tough, but analyzing trace fossils such as nests is especially daunting. Those structures, and the materials used to make them, usually aren’t preserved, says Darla Zelenitsky, a paleobiologist at the University of Calgary in Canada. When paleontologists do find a nestlike structure that includes material such as sticks or other vegetation, the question arises: Was this stuff part of the original nest, or just carried there with the sediment that buried the nest and helped preserve it?

To gain insight into dinosaur nesting habits, Zelenitsky and her colleagues studied the most durable parts of nests—the eggs themselves. (Being largely made of the mineral calcium carbonate, they’ve got a head start on fossilization and are sometimes incredibly well preserved.) In particular, the team looked at the size and arrangement of small pores in the ancient shells, because those details are telling in modern creatures.

In crocodiles’ buried nests, the heat needed to incubate the eggs comes from decomposition of overlying organic matter or the sunlight absorbed by the soil. Plus, in buried nests airflow is somewhat limited, thus requiring eggs to be relatively porous to help increase the flow of oxygen into and carbon dioxide out of the eggs. But birds that brood in open nests can get by laying eggs with fewer or smaller pores.

So the team compared the porosity of eggshells from 29 species of dinosaurs (including large, long-necked herbivores called sauropods; bipedal meat-eaters called theropods; and duck-billed dinosaurs) with that of shells from 127 living species of birds and crocodiles.

Most of the dinosaur eggs were highly porous, suggesting that they buried their eggs to incubate them, the researchers report online today in PLOS ONE. But some of the dinosaur species in one group—a subset of well-evolved theropods considered to be the closest relatives of modern-day birds—laid low-porosity eggs, which suggests they incubated their eggs in open nests.

“This is a well done paper; the results make a lot of sense,” says Luis Chiappe, a vertebrate paleontologist at the Natural History Museum of Los Angeles County in California. The findings, he says, line up other studies suggesting that some birdlike dinosaurs were warm-blooded, which would have enabled them to incubate eggs in an open nest rather than depend on rotting vegetation or sunlight. Chiappe adds that the trend toward open nests could have allowed some dinosaurs to take another step toward birdlike nesting by moving their nests into the trees.

But considering only two types of nests—open versus buried—may be too simplistic, suggests Anthony Martin, a paleontologist at Emory University in Atlanta. Some dinosaurs—like a few of today’s birds—may have nested in burrows, which could have offered the stable temperature and protection from predators of a buried nest but resulted in low-porosity shells. Also, covered nests come in different types: Loose vegetation piled atop a buried nest can have a lot of airflow through it, allowing eggs to have relatively small pores, whereas eggs buried in soil or similar materials might not breathe as well and thus require larger pores, he notes. Nevertheless, Martin adds, the team’s study “is a good first start toward answering the question about what early dinosaur nests looked like.”

See also here.

The findings were published online on Nov. 25 2015 in the journal PLOS ONE.

Turtles are key to tracing birds’ ‘redness gene’ back to the dinosaurs: here.

Saving Cuban crocodiles


This video says about itself:

Cuban Crocodile (Crocodylus rhombifer)

17 October 2011

Watch the Cuban Crocodile and learn how to recognize its unique characteristics. This video captures behaviors and identifies the size, shape and distinctive markings of the Cuban Crocodile. The Cuban Crocodile can be found in the wild and at a number of zoos around the world. Our Cuban Crocodile video is an ideal study guide for students, kids and children who want to learn more about wild animals.

From Phys.org:

April 19, 2015

Kids of Cold War crocs going to Cuba on conservation mission

Cuba’s efforts to sustain the critically endangered Cuban crocodile are getting a boost from Sweden, home to a pair of reptiles that Fidel Castro gave to a Soviet cosmonaut four decades ago.

A Stockholm zoo on Sunday is sending 10 of the couple’s children to Cuba, where they will be placed in quarantine and eventually released into the Zapata Swamp, said Jonas Wahlstrom, the zookeeper who raised them.

“It’s the dream of any zoo director to be part of releasing animals into the wild,” said Wahlstrom, 62, clutching one of the stout-legged youngsters outside its enclosure at the Skansen aquarium and zoo in Stockholm. The 10 crocodiles each are about 1 ½ years old and a meter (yard) long.

The Cuban crocodile, once found across the Caribbean, is restricted today to two swamps in Cuba, where it is threatened by interbreeding with American crocodiles, habitat loss and illegal hunting.

Wahlstrom said he received his original couple during a 1981 trip to Moscow. They had ended up in the Soviet capital after Castro gave them to cosmonaut Vladimir Shatalov in the 1970s as a token of friendship between the communist nations.

“He (Shatalov) brought them back to Moscow and he had them in his flat until his wife said: ‘No more!’ And then he had to give them to the zoo in Moscow,” Wahlstrom told The Associated Press.

But the zoo officials didn’t have a good space for the aquatic reptiles so they asked Wahlstrom if he could take them to Sweden.

“I had them as my hand luggage back from Moscow,” Wahlstrom said.

Zoo officials in Moscow confirmed the background of the crocodiles and their handover to Wahlstrom.

Later named Hillary and Castro—in a nod to international politics—the two crocodiles have become a star attraction at Wahlstrom’s zoo, where they have been breeding since 1984.

Wahlstrom said he’s sent hatchlings to zoos worldwide, but this is the first time he’s given any to Cuba for introduction into the wild.

Cuba’s representative to Sweden welcomed the move.

“We need this type of crocodiles,” Cuban Ambassador Francisco Florentino said as he inspected the animals before their departure Sunday.

With only about 4,000 animals remaining in the wild, the Cuban crocodile, or Crocodylus rhombifer, is red-listed by the International Union for Conservation of Nature. The population is restricted to Cuba’s Zapata Swamp and the Isle of Youth.

This would be the first time that Cuban crocodiles raised abroad are introduced into the wild in Cuba, according to Natalia Rossi of the Wildlife Conservation Society. She’s been involved in other efforts to protect crocodiles in the Caribbean island nation but not the Swedish project.

However, the crocodiles first would be genetically screened to ensure that they come from a pure breed, Rossi said.

The Cuban crocodile can be distinguished from its American cousin by the way it walks and its characteristic bony ridge behind the eyes. But you cannot distinguish hybrid crocodiles from pure-bred Cuban crocodiles by their appearance, Rossi said.

Wahlstrom said he was sure his crocodiles were pure Cubans and expected them to adapt quickly to the real world.

“A crocodile is always ready for the wild,” Wahlstrom said. “They are always aggressive.”

As if to emphasize his point, the baby croc he was holding briefly writhed out of his grip and snapped at an AP journalist’s jacket.