Teachers’ Lounge

Archive for May, 2009

Bird of the Month: Which hummingbird did we spot?

by ocarmi on May. 29th, 2009 3 Comments

About this column>>

I received the following comment in response to my February entry on hummingbirds:

Daniel Kreeger and Mom on May. 24th, 2009 at 7:31 AM:

‘We saw the most extraordinary hummingbird this morning. I had never seen it, but my kindergartner said he was very close to one in Sacramento…(he says “I was so close and it was so cool”) it was completely black, but for a bright red head. Anyone know what we saw? Thanks!’

I thought it would be worth sharing my response with all readers of this column.

partially silhouetted male Anna's Hummingbird
Partially silhouetted male Anna’s Hummingbird
Photo credit: “stonebird,” Inglewood, CA
‘Dear Daniel Kreeger and Mom!

You are a very observant pair!

I do not know for certain what species of hummingbird you saw. However, I can make a good guess. First, though, I’d like to offer some background.

The colors of hummingbirds are special. Much of their plumage is iridescent, meaning that as the angle of light hitting it changes, the color we see changes. This is unlike the non-iridescent reds and yellows and the blacks and browns we often see on birds such as finches and sparrows, which are caused by deposition of various kinds of pigments in the feathers. Iridescent colors, by contrast, result from the structure of the feathers. (Refraction and reflection of light off these feathers cause interference between different wavelengths of light, and thus, at different angles, only particular wavelengths of light are visible).

While iridescent coloration can be very showy—and male hummingbirds make the most of their iridescent coloration in displaying to females—the angle of the light must be right for us to see the color. At some angles, iridescent feathers will appear to us black.

A good example of this is the picture on the right of the head of a a male Anna’s Hummingbird. The entire cap and throat (or “gorget”) should appear to us pink, but notice how much of the head appears blackish-brown—the result of seeing it ‘at the wrong angle.’

I flipped through some field guides to hummingbirds to see if there are any black hummingbirds. There are over 300 species of hummingbirds! Most of them are restricted in range to South America, Central America and Mexico. Only a small number occur in the United States, and just a handful in the Bay Area.

male Anna's Hummingbird
male Anna’s Hummingbird (Calypte anna)
Photo credit: Len Blumin, Mill Valley, CA
There are a few hummingbirds that have extensive black coloration (or, at least, what appears to human beings to be black—because birds can sometimes see wavelengths of light that we cannot). However, none of the hummingbirds that occur in the U.S. are black. So, I find it unlikely that you saw a black hummingbird. More likely, you were lucky enough to observe one of the effects of iridescent structural coloration—you took the time to look, and you noticed that a bird that should be resplendent can appear black—pretty cool!

Now, which hummingbird did you see?

male Anna's Hummingbird
male Anna’s Hummingbird
Photo credit: “randomtruth”
male Calliope Hummingbird
male Calliope Hummingbird
Photo credit: “prayingmother”
male Black-chinned Hummingbird
male Black-chinned Hummingbird
Photo credit: Marj Kibby, Newcastle, Australia
The most typical hummingbird in the Bay Area—and the only one we can see year-round—is Anna’s Hummingbird (Calypte anna). Also nesting here is Allen’s Hummingbird (Selasphorus sasin), and a common migrant is the closely related (and very similar-looking) Rufus Hummingbird (Selasphorus rufus). Occasionally, we see other species of hummingbirds here. Though I have never seen it myself, the Calliope Hummingbird (Stellula calliope) occurs as a migrant in the spring, typically in inland chaparral. Going further inland—to the Sacramento delta—another species that can be found in the spring and summer is the Black-chinned Hummingbird (Archilochus alexandri). One winter, a vagrant Costa’s Hummingbird (Calypte costae) graced my neighborhood in Berkeley; and I’m sure there are many more instances of locally rare or vagrant hummingbirds that I’ve either forgotten, or haven’t heard of.
male Allen's Hummingbird
male Allen’s Hummingbird
Photo credit: “sgrace”
male Rufous Hummingbird
male Rufous Hummingbird
Photo credit: “ianredan”
male Costa's Hummingbird
male Costa’s Hummingbird
Photo credit: Christopher Fritz, San Diego, CA
However, the only locally common species with a completely red head is Anna’s Hummingbird, and that is the species I think you saw.

Thank you for sharing your story. Good observation skills! Let me know if you come up with a different conclusion as to what you saw!’

Incidentally, blue feather coloration is also generally a structural color. In this case, the structure of the feather tissue absorbs most wavelengths of light, but scatters the shortest (blue) wavelengths. That means that we will only see the color when the light rays that reach our eyes are ones that have been reflected off the bird. Compare the two pictures of a Western Scrub-Jay below. In the one on the left, the sun is behind the bird, and we cannot see its blue color. In the other, the sun’s rays are reflecting off the bird, and the and we can see the blue in all its glory!

Scrub-Jay in shadow of sun
Western Scrub-Jay (Aphelocoma californica)
Photo credit: Sandy Harris, Central Coast, CA
Scrub-Jay in full blue glory
Western Scrub-Jay (Aphelocoma californica)
Photo credit: Debra Roby, Hercules, CA

11 Citizen Science Projects in the Bay Area

by sarah on May. 18th, 2009 2 Comments

There are dozens (possibly hundreds) of active citizen science projects out there. This short list provides a small sample of the diversity of projects available for you to involve your students in. Many of these projects also make the collected data available on their website so that anyone (including your students) can study it.

Ant Head
1. Bay Area Ant Survey (BAAS)

Project Focus: Ants.

When and where: Any time in the San Francisco Bay Area.

What do the citizens do? Collect ants, record data on where they were found, and send them to the California Academy of Sciences.

What do the scientists do? Your ant will be entered into the AntWeb database, which aims to document ant species worldwide. The Bay Area information is used to track the spread of an invasive ant species as well as the distributions of native species.

Other Info: Free ant collecting kits can be picked up in the Naturalist Center at the California Academy of Sciences. Teaching kits, which include additional tools for collection as well as a microscope and a dichotomous key for your students to identify their own ants, can be rented from our Classroom Kit Program.

Limpets

Project Focus: Marine invertebrates and algae. Acronym stands for “Long-term Monitoring Program and Experiential Training for Students.”

When and where: Any time at certain coastal sites in California.

What do the citizens do? Monitor the distribution and abundance of key species in rocky intertidal or sandy beach habitats. Students gain valuable experience with data collection methods including vertical transects and random quadrats.

What do the scientists do? Regular monitoring helps scientists understand how key species are distributed around the Bay Area, and to track impacts of human activity and natural events (such as large storms).

Other Info: Teachers must attend a training to participate in this project. Special equipment is required and can be purchased, built, or borrowed from LiMPETS.

USB
3. Quake Catcher Network

Project Focus: Earthquakes.

When and where: Any time, anywhere.

What do the citizens do? Become part of a global network of earthquake sensors. The accelerometer in your laptop can act as an earthquake sensor. If you have a desktop computer, a sensor can be attached via a USB port.

What do the scientists do? A dense global network of sensors will provide scientists with more detailed information about earthquakes and could allow for more effective rapid detection and early warning.

Other Info: K-12 educators can purchase USB sensors from the program for only $5. Lesson plans and activities are available on the website. Faculty and students at Stanford University and UC Riverside are involved in the project.

Bee and Sunflower
4. The Great Sunflower Project

Project Focus: Bees.

When and where: Any time, anywhere.

What do the citizens do? Grow a sunflower (seeds provided) and observe bees as they visit the flower.

What do the scientists do? You may have heard about declines in wild populations of bees, but what about urban populations? This project will build data about urban bee populations and how they interact with green areas.

Other Info: This project was started by a professor at San Francisco State University. The website includes a teacher page with lesson plans, ideas, and other resources.

Baby birds
5. NestWatch

Project Focus: Birds.

When and where: Any time, anywhere in North America.

What do the citizens do? Monitor birds’ nests that you find in your area. Use resources on the website to read up on identifying nests and eggs and what information to record.

What do the scientists do? The reproductive success of many bird species can monitored using the submitted data. Records submitted on paper over the past 40 years are being added to the database, creating a long-term picture of bird breeding and distribution.

Other Info: Be sure to read up on how to monitor nests without disrupting or endangering their occupants before you get started.

Cardinal
6. Great Backyard Bird Count

Project Focus: Birds.

When and where: This is an annual event; the next one takes place February 12 – 14, 2010.  You can participate anywhere in North America.

What do the citizens do? Spend 15 minutes (or more) counting birds. Record the numbers and species that you see and submit the data.

What do the scientists do? This annual snapshot of bird populations and distribution allows scientists to track changes in distribution, declines in populations, and shifts in the timing of migration.

Other Info: Tips for involving students and suggested classroom activities are available on the website. Photo galleries showcase pictures taken by participants.

Birds
7. Celebrate Urban Birds

Project Focus: Birds.

When and where: Any time, any urban area in North America.

What do the citizens do? Learn about 16 types of birds often found in urban areas. Then choose an area to observe for ten minutes and record the birds that you see.

What do the scientists do? The project is focused on urban green spaces and their effects on certain types of birds. Data collected helps determine how birds use different types of green spaces.

Other Info: Starter kits and other resources can be ordered or downloaded and are available in both English and Spanish. Art activities, gardening tips, and community-building ideas are also featured on the website.

Poppy
8. Project BudBurst

Project Focus: Plants, phenology.

When and where: Any time, anywhere in North America.

What do the citizens do? Learn about phenology, the timing of life-cycle events. Select a plant to monitor and record the date of events such as the first leaf, the end of flowering, or the first ripe fruit.

What do the scientists do? Data collected through this and other projects helps scientists understand how climate change is affecting phenology and how changes in phenology can affect ecosystems.

Other Info: Supplemental resources for educators, including lesson plans for classroom activities, will be available on the website.

toad
9. Frogwatch USA

Project Focus: Frogs and toads.

When and where: Any time, anywhere in the United States.

What do the citizens do? Use resources on the website to learn about the frogs and toads in your area and train yourself to recognize their calls. Choose a site to monitor and record the species that you hear there.

What do the scientists do? The data collected by this project can be used to monitor frog and toad populations, species diversity, and other information that can help inform conservation efforts.

Other Info: Amphibians are very sensitive to climate change and are suffering remarkable rates of population decline, making the information generated by this project especially valuable.

Light Pollution
10. GLOBE at Night

Project Focus: Light Pollution.

When and where: This is an annual event taking place in March. You can participate anywhere of the 110 participating countries (including the United States).

What do the citizens do? Observe the constellation Orion. Record which stars you can actually see. Dimmer stars may be obscured by light pollution.

What do the scientists do? Observations reported from around the globe can be used to study light pollution and population patterns.

Other Info: Family activity packets and teacher activity packets can be downloaded in several languages. 2009 has been named the International Year of Astronomy, so this would be a great time to participate.

Galaxy
11. GalaxyZoo

Project Focus: Classifying galaxies.

When and where: Any time, anywhere.

What do the citizens do? Look at pictures of galaxies on the GalaxyZoo website and classify them based on characteristics such as smooth vs. rounded, spiral vs. not spiral, and so forth.

What do the scientists do? The database of volunteer-generated classifications of galaxy characteristics has been used to answer (and raise) questions such as whether more spiral galaxies tend to rotate clockwise or counter-clockwise. New objects spotted in the photos by citizen scientists have been the subject of follow-up investigations, including a mysterious object first noticed by a teacher.

Other Info: With millions of images of galaxies collected by robotic telescopes, professional astronomers certainly needed a little help from citizen scientists. The user-friendly (and surprisingly addictive!) GalaxyZoo website guides participants through simple steps to classify the images. While this project doesn’t meet the goal of getting your students outside, it’s still a fun and rewarding way to supplement your astronomy curriculum.

If you’re not satisfied with only eleven suggestions, visit Citizen Science Central to find more. They have an extensive database of active projects, as well as a “toolkit” of resources for developing and supporting new citizen science projects.

Speaking of new projects, keep your eyes open for new citizen science projects coming soon from the California Academy of Sciences, including one focusing on spiders!

No Child Left Inside

by sarah on May. 18th, 2009 3 Comments

Students at Crissy Field

Last month, five scientists spoke to an audience of teachers about conservation biology during an all-day event called BioForum. The day ended with a panel question and answer session. During this lively conversation between the teachers in the audience and the scientists on the panel, a theme began to emerge: our new policy in science education should be “No Child Left Inside.”

Why is this so important? Several of the speakers agreed that their passion for science was first sparked by spending time outside as kids—“mucking about” in the natural world, exploring and experiencing, developing a life-ling curiosity and fascination with nature that led them into their current careers.

But with so many demands on our class time, how can we justify taking time out to turn our students loose in the great outdoors? From this question, the conversation turned to citizen science projects as a way to give students the chance to spend time in a natural setting, but with content, structure, and value built into the experience.

So what is citizen science, anyway?

Imagine a scientist who is studying, for example, birds. Suppose the scientist focuses on a migratory bird species, and needs to figure out when and where it goes on its migration. If the bird species has a small population in a restricted area, it might be feasible to go out and watch the migration first-hand. But what if the species is spread all across the continent? How can the scientist follow all these populations at once?

Student using Binoculars

One day the scientist realizes that she is not the only person paying attention to birds. There are thousands of amateur birdwatchers across the continent who like to keep track of the birds they see in their area. Whether individual watchers record what they see in pictures, words, or not at all, the combined observations of thousands of people contain a wealth of data with great potential.

Recognizing this potential, the scientist reaches out to the birdwatchers. “Hey guys, if you happen to notice this type of bird passing through your area, can you tell me about it?” Before she knows it, she receives hundreds of sightings from around the country and has all the data she needs to complete her research.

Meanwhile, birdwatchers from different areas are suddenly united and start to compare notes. Instead of making their observations in isolation, the birdwatchers are now part of a community with a common interest and a shared task.

The scientist gets to use the data to map out migratory route of the birds and publishes a paper. The birdwatchers get to see the observations made in their own backyards shared with the entire scientific community. Everybody benefits from the experience—including the birds.

Sounds interesting, but how does that help my students?

Okay, suppose you are starting a unit on birds. You can talk about them, show your students pictures and videos, but you know the best thing would be to take your students outside and show them real birds in action.

Then you hear about the scientist collecting observations from birdwatchers. You realize that this is the perfect opportunity for your students: not only will they get to learn about birds, they will be participating in real scientific research. You can teach them observation and data-collecting skills in a real-world context. Then your class can follow the project and see what happens to the data they send in, giving them front-row seats to science in action.

This is an excellent way to bring your students outside. So much of our teaching takes place indoors, and of course our lectures and lab activities are essential for students to learn science content. But true science is not confined to indoor settings. Science is all about understanding the world around us, and the best way to do that it is to go out into the world and experience it. While most students imagine that scientists spend their whole careers in the lab, the fact is that many scientists spend significant time outdoors doing field work. Involvement in citizen science allows your students to experience this firsthand.

Galaxy Bird Sunflower

That’s great, but what if we’re not studying birds?

This hypothetical example is only the tip of the citizen science iceberg. A vast array of projects are underway involving volunteers, teachers, and students in collecting valuable data on just about everything, from birds to bees and beyond. Citizen science is not limited to biology either; projects exist focused on weather, light pollution, astronomy, and more. Many of these projects are producing real-world results with remarkable impact.

For example, the Christmas Bird Count, which is the oldest citizen science project in existence, has had some remarkable impacts. Data collected by volunteers during 109 annual Counts since the tradition began in 1900 provides scientists with a long-term picture of bird populations and how they change over time. This project documented a significant decline in populations of the American Black Duck in the 1980s, leading to new conservation measures to protect the species.

Citizen science is more than just a way to teach your students science content and science skills; it’s also a way to involve them in valuable work that can make a genuine real-world impact. I’ve compiled a list of 11 Citizen Science Projects in the Bay Area with which you can involve your students.

“Tell me and I forget. Teach me and I remember. Involve me and I learn.”
Benjamin Franklin

Inspirational thoughts and practical tips

by megan on May. 12th, 2009 No Comments

Share Your Ideas

How can we minimize our impact on the planet? What difference can a single person make?

Your students can contribute to this media-rich message board of inspirational thoughts and practical tips. Write a note, post a photo, draw a picture, or even upload a video!

As an individual or with the class, why not share your ideas with others?

Bird Vocalization of the Month: Chicks of the Season

by ocarmi on May. 1st, 2009 No Comments

Species: Bushtit (Psaltriparus minimus); Chestnut-backed Chickadee (Poecile rufescens); Dark-eyed Junco (Junco hyemalis)
Sounds: Bushtit adult and fledgling calls, Chestnut-backed chickadee nestling begging calls and (adult?) defensive noises, Dark-eyed Junco song and fledgling calls (1, 2).

About this column>>

Bushtit
Bushtit Psaltriparus minimus
Photo credit: sgrace
One challenging part of identifying birds by sound is identifying the calls of young birds—nestlings and fledglings. Nestlings are birds that have hatched and grown a little, but are not yet capable of leaving the nest, and fledglings are birds that have developed enough to be able to leave the nest, but are still guarded and fed by their parents. Parents tend to keep their young well-hidden, to protect them from predators. In addition, the calls of young birds can be very subtle—also as a protection against predators.

However, the young of some species of birds are relatively conspicuous, and some have distinctive vocalizations. I’ve decided to feature three such species of birds that happen to be breeding in the Bay Area right now, so that you’d be able to go out and look for them with some possibility of success!

Bushtits (Psaltriparus minimus) are tiny, grey birds that seem to constantly jump about and make soft, pattering calls. In the winter, they may gather in large flocks of up to 75 individuals! However, during the breeding season, much smaller groups can be seen—a male and a female, sometimes assisted by young males born the previous year. Breeding birds construct incredible, sock-shaped, hanging nests of soft plant materials and cobwebs. These nests can take several weeks to construct! I photographed the nest pictured to the right on a recent local birdwatching trip. They are some of the easiest nests to locate around here—they are often placed in Live Oaks.
Bushtit nest
Bushtit nest in dead branches
of oak tree

While all Bushtit calls are rather soft and subtle, there is a distinct difference between the calls of the adults and the calls of the young. Listen to the calls of these adult Bushtits, which I recorded in Golden Gate Park (amidst the noise of cars and other birds!), and compare them with the calls of these fledgling Bushtits, which I managed to record near the campus of San Francisco State University. Notice that the calls of the young are much faster, and seem to consist of a repeated cascading pattern.

I spent a great deal of time trying to find young Bushtits this early in the season, so as to be able to post their calls on this blog entry. In my (brief) experience as a birdwatcher, the sounds of nestling and fledgling Bushtits in the Bay Area become suddenly apparent en masse right around May 1—so prick up your ears! This is the moment to listen for them!

Another local bird whose young produce distinctive vocalizations, and which fledges around this time of year (in fact, often slightly earlier than Bushtits), is the Chestnut-backed Chickadee (Poecile rufescens).

Chickadees nest in tree cavities, and I suspected I had come across a Chestnut-backed Chickadee nest-cavity one day on campus last week, when I heard these Chickadee begging calls. However, as there were no adults around, I couldn’t confirm my suspicion. I returned later, but by this time it was already dark. Resting my microphone against the cavity elicited this response, which I conjecture was a defensive sound produced by one or both parents brooding the young (keeping them warm). I have never heard this sound before, but have since been told that chickadees will hiss at nest intruders.

The following day I managed to confirm that the nest cavity was that of a pair of chickadees. I took the following pictures of one of the parents with food in its mouth about to enter the cavity (which lies out of view to its right), and of several begging nestlings within the cavity, necks stretched upwards, and gapes wide open. Note the yellow color at the base of the nestlings’ bills. Colorful gapes are thought to facilitate feeding of the young by adults.

[By the way, I featured some calls of adult chickadees in my March entry, “Mid-March Medley.”]

Chickadee with food
Chestnut-backed Chickadee
parent with food
Chestnut-backed Chickadee nestlings
Chestnut-backed Chickadee nestlings
in tree cavity

The final species I will mention today is the Dark-eyed Junco (Junco hyemalis), which nests on the ground in thick ground cover or leaf litter. Juncos are often found in human-altered habitats. As an example of where you might find Junco fledglings, I took this (poor!) photo below of a fledgling on the San Francisco State University campus: the habitat in this case consists of a ground cover of non-native English Ivy with scattered non-native shrubs.

Dark-eyed Juncos produce a variety of vocalizations. The frequently heard song of the male Dark-eyed Junco consists of a long trill. The begging calls of the fledglings are somewhat variable, but these dry rattles are typical. These ticking calls, which resemble the calls of adults, are also typical begging sounds.
Junco nesting habitat
Junco fledgling in English Ivy
ground cover
Adult Dark-eyed Junco
Adult Dark-eyed Junco (Junco hyemalis)
Photo credit: Marcus Smith, Los Angeles
If you happen to watch birds this time of year, please note that the fledglings of Chestnut-backed Chickadees and Bushtits greatly resemble adults in appearance. Young juncos, however, look quite different from adults. Adults, in our area, have dark hoods, brown backs, and light bellies, whereas fledglings are covered in streaks.

Go out there and find some young birds!

Your homework assignment: I posted some rather subtle recordings in this entry! If you feel motivated, listen to them, and familiarize yourself with the sounds of nestlings and fledglings likely to be encountered at this time of year; then pay attention while you’re out and about in case you hear one of these sounds.

However, I have an additional suggestion this time around: Pay attention to the world around you with all your senses! While preparing this blog entry, I heard a sound I had never heard before (the hissing of chickadees at their nest)! It pays to listen! But also keep your eyes open—there is little that is more heartwarming than a parent bird feeding young. Especially at this time of year, when you hear birds, look, and when you see birds, follow them with your eyes. Incessantly calling birds may turn out to be begging fledglings (fluttering their wings and pursuing adults), and if you watch them long enough, you’ll see them get fed.