Warm Autumn Impacting Tortoise Hibernation

There are signs of autumn all around. The leaves of the peach tree are daily turning red and golden.

The toyon fruit (aka California holly) is turning red and attracting the attention of the hungry hermit thrush.

But the on-again, off-again autumn weather is making someone grumpy. The angle of the sunlight signals autumn–time to hibernate–but the warm days keep tempting the desert tortoise to stay up.

As you can tell from the photo, this guy is not asleep. His son, has gone in for the winter. Typically, the old guy is in by mid-October, but this year he can't seem to commit to hibernation. He comes out, sits in the sun, takes a few bites of food then grumbles back into his den. Today he stuck his head out and immediately turned around.

He wants to be asleep, but the warm weather is confusing. Some of the migrating birds have been off in their annual cycles as well. For this desert tortoise who has been in captivity, since the mid-1970s, fluctuating climate is an irritation, but for desert tortoises in the wild there can be serious consequences. If they miss time hibernation, they can get caught away from a protective den when the weather does turn cold. They could use up food reserves before they hibernate.

They do not digest food well without basking in the sun and having hot temperatures. They need to stop eating and completely digest what is in their stomachs before going into a deep sleep. Undigested food in their system can rot while they are hibernating, causing them problems. When tortoises awaken in the spring they have expectations of flowering plants and new greenery that they depend on to replenish themselves after months of not eating or drinking. Changing climate can impact all of the timing in this delicate dance making survival even more of a challenge for wild tortoises.

This grumpy guy has us as caretakers to make sure he has food and vitamin supplements. Wild desert tortoises are on their own. Tortoises around the world need our help. They are important members of their ecosystems and all too frequently they are taken out of the wild, both to their detriment and that of the other plants and animals that depend on them.

Tortoises in Turkey
I recommend book Life in a Shell

Thanksgiving Toyon

There is a special reward for planting native plants: watching habitat being restored in front of your eyes.

Five years ago I planted a 3 gallon toyon (Heteromeles arbutifolia). It started out just 2 foot tall. Today it is about 8 foot tall. The dark green leaves are prickly and in late autumn its berries ripen to a brilliant red. It's no wonder European immigrants to California were reminded of holly and called it "California holly" or "Christmas berry."


In fact this is the holly that gave the name to "Hollywoodland" and therefore Hollywood. (Decorating with toyon)

The native Chumash, Ohlone and other coastal peoples in California roasted or dried the berries and ate them. They also used the strong, rot-resistant wood for a variety of implements and ceremonial markers. But people weren't the only species that depended on the toyon. Numerous animals eat the berries as well, rodents, foxes (including the endangered island fox), probably the extinct southwestern grizzly bear did as well. A wide range of birds also look for this easy-to-spot, chaparral delicacy. 

Sunday morning I watched the hermit thrush picking one red berry at a time and swallowing it down. A hermit thrush has been coming to my yard every winter for the last seven years. I believe it is the same bird, but I don't absolutely know that for sure. For the second year in a row it arrived with a friend. I wonder if the thrush has been waiting for the toyon to grow up and become the beautiful berry-producing plant that it is now?

One thing is for sure, the toyon has created a valuable source of winter food for the hermit thrush, cedar waxwings and other berry-eating birds. The hermit thrush seemed to be thankful for its bountiful meal and I was heartened that I had made a positive difference for the local wildlife and migratory birds.

Now is the season in California to plant native plants, they are the Foundation of Habitat. Plant a few natives and help make a positive difference.

Signs of Autumn

The signs of autumn are different here in California. While snow is falling in some parts of the country, our insects like the preying mantis are still finishing up their life cycles. This female laid her egg mass on a grape vine. She camouflaged it perfectly to give her offspring the best chance at success, because while they over winter, she will not survive the cooling nights.

But autumn is the time of rebirth for our native plants. The hot dry summer is to hard to survive. Native plants take the summer off, going dormant. This is what many people expect for winter, but as the days shorten and the temperatures cool, native plants begin to grow again.

The ribes or wild currant was covered with dried brown leaves, but autumn growth is bursting out in bright green and pushing aside the old leaves.

Toyon berries are beginning to swell.

Even introduced plants have adjusted to California’s seasons. The bell-shaped blooms on the strawberry tree are popping open.

And the camillia is forming flower buds that will bloom in the middle of our mild California winter.

Migrating birds are traveling through and the Cooper’s hawk, a fast flying aerial predator is hanging around bird feeders. I had a Cooper’s hawk catch a mourning dove in my yard this week. My friend Douglas Welch caught the following video in his yard. It is a great opportunity to compare this fast hawk to your birding books. It is an immature individual which can be tricky to identify.



Check out what is happening in Douglas’ backyard at A Gardner's Notebook

The Juncos Have Arrived

The Oregon juncos arrived today. Amazingly, they are only a day earlier than last year. The two males arrived thirsty and spent some time drinking at the bird bath, which is rather unusual for them. These two males have been winter residents for the past couple of years. There will be other groups with males and females, but these two males arrive first and they always seem to be together. More on that later.

The white-crowned sparrows should be here within the week.

Warblers and Weather

Something is in the air. It isn’t just autumn and it isn’t just smoke from the Station Fire. (Which is still burning in the Angeles Forest).

We are seeing a number of migratory bird species that we typically do not see in autumn:

• Cassin’s kingbird (previously 12/06)
• warbling vireo (previously 4/07)
• Wilson’s warbler (annually, February and May)
• black-headed grosbeak (annually, April to early August)

If it were just one unusual siting, I wouldn’t think much of it. A Wilson’s warbler arrived last week. After seeing it in the yard, I later found it sitting on the window sill. It seemed exhausted and gagging on our smoke-filled air. I easily scooped it up and brought it inside for a few hours. It was out of my cage in a moment, (they are smaller than you think), and it spent the day sleeping perched on a quiet bookshelf. In the late afternoon, we opened the window and gently shooed it out.

I was thrilled, this morning when three warbling vireos passed through the yard. They stopped for food and water. But it made me start to wonder: Why are we seeing these birds?

Would they usually stop in the Angeles Forest and they’ve found the habitat they depended on gone? All of the birds I have been seeing are species that have been here in our yard before, just at different times of the year. Are they individuals that remember this place?

But, none of these birds have been ash-covered. Two years ago following the large fires to the north of us, birds migrating south that stopped here were covered in ash, exhausted and hungry. Every time a new group arrived, we had a to clean the film of ash out of the bird bath. That isn’t happening.

When I looked at my past bird logs, I found that September of 2005 also had a variety of birds, migratory and non, that were unusual: a Costa’s hummingbird, house wren, song sparrow pair, brown-headed cowbird, a very late hooded oriole, and a black-headed grosbeak. The black-headed grosbeak made me wonder about the weather in 2005.

But the September weather in Woodland Hills in 2005 had a median low of 56˚F and a median high of 85.5˚F, while this year, 2009, the temperatures have been much higher: median low 62˚F and median high 95˚F. The winter of 2005 was cool, but dry. That isn’t what we are hoping for this winter.

Another marker of 2005 was that the white-crowned sparrows arrived very early. Rather than mid to late October, the white-crowns arrived on September 30th. It will be interesting to see when they return this year. 2008 white-crowns return

The meteorologists are predicting a wet El Nino year. Do the birds know better? Are we in for another cool, but dry winter?