Monday, July 23, 2012

Red-tailed Hawk in the Bird Bath

This morning a new youngster was dropped off by its parents. Yes, the bird bird sitting on the bird bath is a juvenile, a red-tailed hawk that has just recently left the nest. Unlike its parents, the tail of the juvenile is not a rufous red, but dark brown and somewhat banded. The overall coloring is also more mottled and streaky than the parents, providing camouflage as it sits waiting for its parents to return with food.

It is actually interesting how similar the coloring is between the juvenile Cooper’s hawks and this red-tailed hawk. The Cooper’s hawk kids are now spending their days with their parents. However, they drop by for a drink or a rest during the day.

But this new baby that has taken their place is at least 4 times the size. The large size of this juvenile red-tailed hawk suggests that it is a female; female birds of prey are typically larger than males. In the Los Angeles area this is the largest hawk species that we see. Typically, they are the large hawks sitting on lampposts along the freeway looking down into landscaped areas for rodents of all kinds: squirrels, rats, mice. They are rodent specialists.
When the red-tailed hawk took a bath this morning, she filled the whole bowl.

As she sat preening on the wires above the bird feeders, she had an audience of smaller birds and a squirrel watching her.

The birds interest her, but they are typically to small and fast to be considered prey. The fox squirrel, however, caught her eye.

And then the climbing rodent was concerned that it had. Her parents would have been proud that she focused in on the squirrel.

She must not have had breakfast, because she has steadily called for her parents for the last half hour. I just hope she is better at keeping hold of the food they bring than the young Cooper’s hawks were. Untidy hawklets.

Friday, July 20, 2012

Green Lynx Spider Stalking Yellow Jackets

What killed this yellow jacket wasp?
Yellow jackets are a kind of wasp and many people fear them. Their black and yellow coloration is mistaken for honey bees and people are afraid of being stung. 

We have a low number of yellow jackets in the yard, but when you see them at a protein food source, like a hawk cast, it appears they are numerous. Video. When we first moved to this house 18 years ago, we couldn't eat on our patio without being harassed by 10-20 yellow jackets. We put out traps for them.

The problem was that we didn't have a balanced ecosystem. The previous owners sprayed for insects, baited for snails and planted mostly non-native plants. Gradually we have restored a more natural flora, which in turn attracts native animals–from insects to raccoons.

The Cooper's hawks are feeding their youngsters in the backyard. The young hawks are dropping bits of meat, this feeds the yellow jackets. But the yellow jackets are also eating the caterpillars that show up on my tomatoes. And the yellow jackets have a predator too.
Green lynx spider feeding on a beetle

This lovely green lynx spider prowls the vegetable garden leaving behind the dried exoskeletons of yellow jackets and other insects. Egg sac. We do less and the natural balance of biodiversity does more.

More on California spiders:
red jumping spider
trashweb spider
trapdoor spider 
cobweb spider 

Saturday, July 14, 2012

Insects Feeding on Hawk Leftovers

The young Cooper's hawks are becoming the center of their own ecosystem. Their overworked parents bring food, drop it off and leave again, just that fast. With four juveniles that eat as much as they do, each parent is having to catch three times its normal prey. 

They aren't restricting their hunting to birds, they are bringing back whatever they can find. Rats have definitely been on the menu.

The juveniles eat their fill and then, similar to owl pellets, they cough up clumps of hard to digest bones and fur.

These "casts" are a bit gory, but they are in turn providing food to carnivorous insects like the yellow jackets in the video here. Listen and you will hear one of the young hawks calling in the background. Ants and flies are eating the leftovers, while western fence lizards are then pouncing on both species of insects. Spiders also will benefit. The ring-necked snake benefits from the success of the lizards.

Our yard is alive with biodiversity. Thanks to Eclipse-1 Media.

Wednesday, July 11, 2012

Pre-School for Cooper's Hawks

young Cooper's hawk
The Cooper’s hawks have had a huge family this year. They first mated back in March. They must have lost the first clutch, but they are making up for it. There are four recently fledged juveniles hanging out in the backyard. In the morning and late afternoon they raucously call for their parents to bring them food.

Two of the larger juveniles are starting to follow the parents. It would be fascinating to see if they are watching their parents hunt.

Catching enough food to provision the four youngsters, who are now as large as their parents, is a Herculean task. The parents aren’t being picky about prey; rats have even become part of the fare.

With four youngsters to watch over, it's understandable that while the parents were off with the bigger chicks when they first left the nest, they missed that the little one didn't want to be left behind. The little hawk was not yet able to fly and ended up on a neighbor's front porch, just steps from the sidewalk. The flurry of humans wanted to "save" the little guy. But these hawks are devoted parents, like most birds, I convinced everyone to give the parents time to collect their youngster. I relocated the juvenile a short distance from its landing spot to an area that was away from the sidewalk, shaded yet visible to the parents. The parents did return and communicated to their little one what it needed to do, to get safely up into a tree.

He is flying a little, but still not well enough to follow the parents. The smallest of the juveniles he's pictured here. He's hungry enough that he has started trying to catch his own food. His movements are not skillful and his attempts seem to be in slow motion. He went toward a group of house finches, who stayed just out of his reach, then he turned to go after a fox squirrel. The squirrel couldn’t believe its eyes at first. It moved just out of the young hawks reach, then actually came back to taunt the young bird.

When he isn’t calling for his parents, the young hawk sits watching the small birds that one day will be its food staple. He’s learning how they fly, their alarm calls, how they respond to threats. His sharp eyes are ever watchful.  Cooper's hawk on fountain.

Meanwhile the California towhees are taking no chances. They are teaching their youngster to fly under the covered patio and carport. No use tempting the young Cooper’s hawk to make its first self-caught meal a young towhee just learning to fly.