About

Send your questions to atn@baynature.org.Santa Rosa-based naturalist Michael Ellis leads nature trips throughout the world with Footloose Forays (footlooseforays.com).

Contributions

“By the Wind” Sailors: Seasonal Velella beaching mystery solved

July 30, 2014 by Michael Ellis

Recently, Bay Area beachcombers have been spotting dozens of mysterious blue jelly-like creatures littering the beaches. What are they, and why are they here? Bay Nature naturalist Michael Ellis explains.

12 Comments

Ask the Naturalist: Where Are the Chorus Frog Babies?

October 10, 2013 by Michael Ellis

Q: I collect rainwater to use on my garden and I’ve found Pacific chorus frogs in the black garbage can that collects the rainwater, but I’ve never seen eggs or tadpoles in there. I wonder why not; would they be too small to see? [Marian, San Jose]

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How can you tell male vs female lizards?

July 07, 2013 by Michael Ellis

Q: Is there a way to tell the difference between male vs female lizards? How do they attract their mates? ...

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How do barnacles make baby barnacles?

April 03, 2013 by Michael Ellis

Barnacles are hermaphroditic -- they contain both male and female sex organs. You're thinking, "Well, they always have a date on Saturday night." No, it's a really bad idea to self-fertilize: Inbreeding results in little genetic diversity. Worms, slugs, snails -- slow-moving animals with low rates of encounter -- are all hermaphroditic. And you could not get any slower than an adult barnacle!

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Should we be worried about asbestos in serpentine rock?

January 31, 2013 by Michael Ellis

Should we worry about asbestos in serpentine rock? Yes, a bit. In California, we have North America’s largest exposures. It's even our official state rock.

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Biggest Local Land Invertebrate? The Tarantula

July 01, 2012 by Michael Ellis

Q: What's the largest underground-dwelling invertebrate in the Bay Area? How does it live?

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Why do pelicans fly so low?

June 12, 2012 by Michael Ellis

Learn a few secrets of efficiency from the majestic pelican.

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What’s the secret of nectar?

January 01, 2012 by Michael Ellis

Q: When I see bees and hummingbirds feasting on even tiny flowers, I wonder if each flower replenishes the nectar supply, or is it a one-time offering?

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Can bees see more colors than we can?

October 01, 2011 by Michael Ellis

Can bees see colors that people can't? What about birds? How do scientists figure out what can be seen by other animals, especially small animals like insects?

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Top Shark: This One Goes to Seven!

July 01, 2011 by Michael Ellis

The biggest shark in the Bay is the seven-gill--with two more gill slits than the average shark. Why the extras? Well, turns out they’re probably an evolutionary accident, but these are still fascinating animals--up to 10 feet long, and swimming right out there in the Bay!

3 Comments

Why are barn owls dying on the road?

April 01, 2011 by Michael Ellis

Bay Nature reader Rich saw a number of dead barn owls along I-5. What's going on? Turns out barn owls may be the most widespread birds in the world -- and they may be the original ghosts!

1 Comment

Where are the Ringtails?

January 01, 2011 by Michael Ellis

Michael Ellis declares that ringtails register a 9.9 on the cuteness scale, and they were reputed to shack up with miners during the Gold Rush. Yet longtime field biologist Wendy has yet to see one of these small mammals. They are elusive, but not as uncommon as you might think.

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What are glowworms?

October 01, 2010 by Michael Ellis

We don’t have fireflies in the Bay Area, but we do have glowworms. What are they and why the heck do they light up?

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Was there ever a waterfall at the Golden Gate?

July 01, 2010 by Michael Ellis

Q: Rumor has it there might have been a waterfall at the Golden Gate during the last ice age, when ...

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Why Do Birds Flock?

April 01, 2010 by Michael Ellis

Q: I recently saw a video of a cloud of birds moving in wild patterns. Then I saw shorebirds doing ...

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What’s the deal with pelicans’ weird bills?

January 01, 2010 by Michael Ellis

Can a pelican really hold a week’s worth of food in its bill?

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What is quicksand?

October 01, 2009 by Michael Ellis

The quicksand won't get you, but the quakes might.

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The Longest Haul of Them All

July 01, 2009 by Michael Ellis

Which bird that migrates to or through the Bay Area travels the farthest to get here from its breeding grounds?

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World’s Smartest Molds

January 01, 2009 by Michael Ellis

Watch out for these unusual creatures next time you’re walking in a wet forest.

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The Paranoid Jay

October 01, 2008 by Michael Ellis

Why is this bird attacking my windows?

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Photosynthesis in leaves that aren’t green

July 01, 2008 by Michael Ellis

Q: How does photosynthesis occur in plants that are not obviously green, such as ornamental plum trees with deep purple-colored ...

20 Comments

Why do dragonflies swarm?

April 01, 2008 by Michael Ellis

Q: Last October, while hiking on Mount Tamalpais, near Laurel Dell, I saw numerous swarms of dragonflies. Could you tell ...

67 Comments

What native land snails live in the Bay Area?

January 01, 2008 by Michael Ellis

Q: What native land snails live in the Bay Area? Where do the common garden snails come from, and what’s ...

3 Comments

Are native bees suffering the same colony collapse disorder as honeybees?

October 01, 2007 by Michael Ellis

Q: Are native bees suffering the same “colony collapse disorder” as honeybees? [Linda, San Ramon] A: Colony collapse disorder, or ...

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Do local breeding birds mate for life?

July 01, 2007 by Michael Ellis

Q: Do any local breeding birds mate for life? Why? [Leo, San Francisco] A: Some local birds do form long-lasting ...

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Is it OK to catch crawdads?

April 01, 2007 by Michael Ellis

Q: A group of families goes out every year, catching up to 300 crawdads for a big feast, releasing those ...

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Which spot in the Bay Area gets the most rainfall and which the least?

January 01, 2007 by Michael Ellis

Q: Which spot in the Bay Area gets the most yearly average rainfall and which spot gets the least? Why? ...

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What were those fins off Ocean Beach?

January 01, 2007 by Michael Ellis

Q: Off San Francisco’s Ocean Beach, I saw dorsal fins beyond the surfers. After 20 minutes, I saw two bearers ...

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What is the largest species of fish you could find in San Francisco Bay?

October 01, 2006 by Michael Ellis

Q: What is the largest species of fish you could find in San Francisco Bay? A: Let’s limit ourselves to ...

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When was the last volcanic eruption in the Bay Area? Where was it?

October 01, 2006 by Michael Ellis

You can easily visit the 10-million-year-old Sibley Volcano (see Voice of the Volcano, April-June 2005) in the hills above Oakland. ...

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Why are banana slugs so slimy?

July 01, 2002 by Michael Ellis

Back when I used to teach children about nature, I often relied on a “hook” to keep them focused. Slapping ...

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How have humans influenced wild animal behavior?

October 01, 2001 by Michael Ellis

Most of the world’s 5,000 or so species of mammals are already nocturnal, so the effect of urbanization on their ...

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