Tiny mobsters

Forest walk, Sax-Zim bog, Meadowlands MN

Forest walk, Sax-Zim bog, Meadowlands MN

We got a good demonstration of just how many tiny birds were present in the woods alongside roads in Sax-Zim bog, when our guide (Clinton Nienhaus, head naturalist at the bog) briefly played the call of a Screech Owl.  Within a couple of minutes, dozens of Black-capped Chickadees and Red-breasted Nuthatches appeared, calling continuously to sound the alert of a predator’s presence.

Red-breasted Nuthatch

Red-breasted Nuthatch, one of about a dozen, sounding the alert in response to a Screech Owl call.

Weighing in at a whopping 10 grams (less than a fast-food packet of ketchup), tiny Red-breasted Nuthatches are just a bit smaller than Chickadees, but even a small bird with that sharp-pointed beak could do some damage at close range.  In any case, the point of the mob action is to pester the would-be predator enough that it eventually flies away.  Mobs of small birds may also attract larger birds like jays and crows to help drive off the predator.

Red-breasted Nuthatches mobbing fake owl

Red-breasted Nuthatches and chickadees flit from branch to branch looking for the owl.  Since I have only ever seen a single or a pair of nuthatches at one time, this was a real treat to see so many of them in action.

Red-breasted Nuthatches prefer coniferous woods, like the black spruce and tamarack of the bog.  In the spring and summer, they are highly insectivorous, but like the chickadees, in the winter they love the peanuts and suet found at bird feeders.  Even though they are one of the smaller birds at the feeder, their feisty, aggressive behavior often drives bigger birds away.  Like their cousins, the White-breasted Nuthatch, they will store some of the feeder largesse in tree crevices for a snowy, cold day.

Red-breasted Nuthatch

Looking up, looking down….where is that owl?

Sax-Zim bog is one of the premier birding areas in Minnesota, attractive to a number of Canadian breeding species like the Great Gray Owls and Hawk Owls, as well as northern breeding finches during the winter.  The farm fields filled with hay bales seem to be filled with mice and voles, perfect for raptors, and the dense spruce-tamarack forest provides good cover.  The Friends of Sax-Zim bog have established a welcome center where one can get a map, advice on where to search for some of the more exotic species, and even guided field trips to help you spot those elusive birds.

Field trip Sax-Zim bog, Meadowlands MN

Field trip Sax-Zim bog, Meadowlands MN.  We stopped here to check on the presence of Redpolls and other small finches.  Alas, only one Redpoll appeared, and only very briefly and far away.

For more information about the bog, visit their website (link above) or check out the photos and commentary of one of the founders of the organization, Sparky Stensaas at The Photonaturalist.

Finches of the forest

It was a treat to find two birds we never see in the Twin Cities at the feeders in Sax-Zim bog last weekend.  Evening Grosbeaks and Pine Grosbeaks are the largest members of the finch family, and like other finches, the male is brightly colored and the female is somewhat drab in comparison.

Male (left) and female Evening Grosbeak

Male (left) and female Evening Grosbeak

Male (top) and female Pine Grosbeak

Male (top) and female Pine Grosbeak

Both species use their large, crushing bills to harvest seeds out of reach of the smaller finches in the winter, but the summer diets of both are quite varied.

Male (top) and female Pine Grosbeak

Now that’s a big beak!

Evening Grosbeak

Evening Grosbeaks consume a lot of seeds in the winter, but they are largely insectivorous in the summer, especially when feeding chicks.  They are a major predator of the spruce budworm pest.  They are usually found in spruce-pine forests in southern Canada and the mountains of the western U.S. year-round.

Pine Grosbeak male

Pine Grosbeaks prefer a diet of fruit with their seeds and might feast on crabapples in a residential yard, as well as the sunflower seeds at the feeder.  They breed in the northern-most coniferous forests of Canada, feeding their chicks a mash of insect and vegetation.

The two species are not closely related, and the Pine Grosbeak is actually a circumpolar species, found in pine forests from Scandinavia to Eastern Asia, with its closest relatives being the European Bullfinches.  In North America, both species respond to winter food shortages with irruptive behavior that might involve flying miles south of their breeding territories.  Northern Minnesota is on the southern border of their winter range, so we felt lucky to see them.

…not a creature was stirring…

North of the Twin Cities of Minnesota about three hours drive is a vast boggy patchwork of black spruce-tamarack forest and open prairie/cropland that is the winter home of some of the raptors that breed in the Canadian tundra.  We visited there over the weekend hoping to see a few Snowly Owls and Rough-legged Hawks, the chief avian predators of the open fields between the swampy areas of Sax-Zim bog.

Birch-aspen forest in Sax-Zim bog, MN

We had high expectations of seeing our target species in these open fields on a frosty morning, when the thermometer hovered around 7 degreees F and the tips of the trees were covered in hoar frost.

Hoar frost

What little moisture is in this frigid winter air condenses into icy coatings on exposed branches when temperatures dip below the dew point at 7 degrees F.

Cropland in Sax-Zim bog, MN

Looking high in the trees for the hawks and low on the hay bales for the owls, we traversed the bog and crop lands searching for raptors. A Snowy Owl should be perched on one of the hay bales…

Cropland in Sax-Zim bog, MN

But not a creature was stirring. In fact, there were no birds of any sort flitting about. It was unnaturally still!  Rough-legged Hawks should be perched in one of the trees lining the open fields searching for mice…

Alas, a four-hour search turned up just one hawk, seen at a distance of about 1/4 mile, and no owls.  But there was a lot of photogenic scenery along the way (more on that next time…)

The next day we did find a Rough-legged Hawk perched right by the side of the road, overlooking a farm field of corn stubble, but the bird flew off as we drove up.  It would have been a nice photo op, something like this…

Rough-legged Hawk, Wikimedia Commons, photo by dfaulder

Rough-legged Hawk, (Wikimedia Commons, photo by dfaulder).

Heavily streaked with brown and sporting flashy white tail feathers and densely feathered legs to keep those toes warm in the frigid winter temperatures, these medium-sized hawks hunt for mice in the open fields.  But they will attack most any bird or mammal prey they find, including rabbits and weasels, snow buntings and tree sparrows, even other raptors from whom they may steal the food.  If live food is lacking, the hawks will feed on carrion.

Voles and lemmings make up the bulk of their diet, and there is some evidence that Rough-legged Hawks can actually see the scent marks left in the vole urine which is visible in the UV.  Imagine the hawk’s eyes following trails of blue fluorescing across the snow to where a mouse hides just under the crust.  Bam!  Dinner.

Funny feet

I think of American Coots as very common, uninteresting birds, and so I never photograph them.  But I was intrigued by their diving maneuvers to obtain submerged vegetation, and stopped to watch them more closely on my walk along Los Gatos Creek in San Jose, CA the other day.

Juvenile American Coot

This juvenile Coot was very protective of a small patch of submerged vegetation a foot or so below the surface.

Coots seem to be very buoyant in the water; it takes work to submerge and they actively kick their feet against the water as they dive, quite unlike what Cormorants do.

American Coot diving

This is the intriguing part.  Look at those big feet/toes that the bird uses to propel itself down into the water.

Submerged American Coot

Using their lobed toes to propel them, Coots can get down to choice bites of vegetation.

Juvenile American Coot

Sometimes they bring up a large amount of vegetation that they bite off in chunks.

American Coot feet

A better look at those funny feet.   Photo from http://naturemappingfoundation.org/natmap/facts/american_coot_712.html

Coots occupy a wide variety of wetland habitats throughout North and Central America, feeding on a variety of aquatic vegetation.  But they are not fussy and will eat seeds or invertebrates they find on land as well.  Typically, they forage in small groups, their lobed toes expanded to a web as they kick backward to propel them through the water, and then collapsing inward as they bring their foot forward again.

That lobed toe design comes in handy when Coots walk across muddy, marsh ground, preventing them from sinking down into it.  And they assist Coots in taking off from water, when they need to use their feet to help lift their chunky bodies into the air.

Pretty useful, those funny feet!

American Coot taking off from water (Audubon)

American Coot taking off from water (Audubon Guide to North American Birds).

Drying time

If you’re a busy Cormorant that’s been diving for fish all morning on Los Gatos creek, you need to spend some time drying off before flying on to the next destination.

juvenile Double -crested Cormorant, Los Gatos creek park, San Jose, CA

Diving Cormorants sit very low in the water, all the better to quickly submerge in search of prey.

The reason for the “drying time” requirement is because Cormorants do not water-proof their feathers with an oily secretion as other birds do, which makes it easier for them to stay submerged, dive, and “fly” through the water.

juvenile Double -crested Cormorant, Los Gatos creek park, San Jose, CA

This juvenile Cormorant spotted a potential drying off place, and began to raise itself up to get on the branch.

juvenile Double -crested Cormorant, Los Gatos creek park, San Jose, CA

Even wet feathers can lift the bird a little ways up in the air…

juvenile Double -crested Cormorant, Los Gatos creek park, San Jose, CA

Lots of wing flaps begin the process of drying off…

juvenile Double -crested Cormorant, Los Gatos creek park, San Jose, CA

Really vigorous wing flaps may shake the water off those feathers, but somehow the bird doesn’t lift off the log.

juvenile Double -crested Cormorant, Los Gatos creek park, San Jose, CA

The more typical Cormorant “drying off” pose. This works best where there is a little sun and some wind, neither of which this site on the creek provides.

juvenile Double -crested Cormorant, Los Gatos creek park, San Jose, CA

Finally satisfied with the dryness of its wing feathers, the youngster relaxes and looks around. It is unperturbed by my presence only 20 feet away. I wonder why?

Now it’s easier to see the difference in coloration between this juvenile bird, with its pale throat and chest and brown head, and an adult bird.

Adult Double-crested Cormorant

An adult bird in breeding plumage sports a set of white-tinged crests on either side of its very black head.

Tiny birds

Some of the tiniest birds in the Avian taxonomic class (outside of the hummingbirds) live here in California, and in fact, are quite common in parks and urban areas.  I happened to find one the tiniest species on my walk along Los Gatos creek the other day.

American Bushtit, San Jose, CA

The American Bushtit is the sole representative of its primarily European and Asian family of Long-tailed Tits.  You can appreciate how small it is when you compare it to the leaf of a cottonwood tree.

Bushtits weigh in at a whopping 5.5 grams on average — that’s how much a nickel weighs and is only slightly more than an Anna’s Hummingbird weighs.  Yellow-rumped Warblers seen zooming through our yards on migration every year and Black-capped Chickadees weigh twice as much as a Bushtit.

American Bushtit, San Jose, CA

Usually found foraging in small groups, Bushtits move around so quickly, they make it hard to get a good photo.

Other than being tiny and dull gray, their chief distinguishing feature is a thin, longish, dark tail.  But observing them up close, you learn that Bushtits are very social: they forage in small groups, they huddle together at night to stay warm, and they have “helpers” at their nests that defend the breeding territory and feed the chicks.  Usually these helpers turn out to be lower status males that failed to attract a female or whose nesting attempt failed.  This type of social behavior is more often seen in species in the Jay and Crow family.

American Bushtit, San Jose, CA

This is a female Bushtit, distinguished by her pale iris. The iris changes color a short time after females hatch, making it easy to sex birds in a flock.

Their diminutive size enables them to search small crevices or hang from the flimsiest branches in search of small insects or spiders hiding there.  Bushtits do us a favor by hunting along drooping branches for the scale insects whose excretions leave a collection of sticky droplets on our cars.

American Bushtit, San Jose, CA

Like their Long-tailed Tit relatives in Eurasia, Bushtits weave a hanging nest from a thin tree branch, by using stretchy (and strong) spider web incorporated into plant fibers.  It might take a month for a pair of Bushtits to build the structure, after several trials to determine the best location.

Bushtit nest, WA, photo by Mike Hamilton

Bushtit on its nest, photo by Mike Hamilton, in Washington state. https://www.birdnote.org/show/bushtits

Bushtits probably originated from Asian Long-tailed Tit species, spreading down the coast of western North America from Alaska to Mexico sometime after the Pleistocene glacial period. Their small size and group social dynamic may have been a key to their success in exploring a new niche in the “New World”.

a California fall day

Back in California for a couple of weeks, for a wedding and to enjoy prolonging lovely fall weather as long as possible.  It was a good day to hike along Los Gatos creek in Campbell (a small municipality in San Jose, CA) and enjoy the local wildlife.

Los Gatos Creek Park, Campbell CA

This pond along Los Gatos creek trail supports an amazing diversity of wildlife, from tame Mallards and Peking ducks, to breeding colonies of Cormorants, a pair of kingfishers. various Gull species, and of course, Canada Geese.

Los Gatos Creek Park, Campbell CA

There hasn’t been any rain here yet and most of the landscape is extremely dry except bordering the creek itself.

Common Bushtits, Los Gatos creek park, San Jose CA

Five little Bushtits looking for bugs on the dried wild anise. Can you find all of them? (I didn’t take the telephoto lens on my walk today.)

More on the Los Gatos creek wildlife in the next post….

Fruit feast

Trees and shrubs are dripping with fruit and berries this fall, and the robins are loving it.  A migratory wave of the feisty chirppers arrived this past week to attack the crab apple crop.

American Robin in a crabapple tree

With this many fruits to choose from, this Robin must be overwhelmed with the sea of red.  

But not all fruits on the crabapple tree are equal, and Robins prove to be quite choosy about which fruits they select.

American Robin in a crabapple tree

This one?

American Robin in a crabapple tree

Nope, this one instead. Notice it’s kind of shriveled and wrinkled looking.

American Robin in a crabapple tree

Down it goes, and the search for the next (ripe?) fruit begins.

The firm, plump red crabapples area definitely not the desirable ones. Are the wrinkled ones sweeter, or are they a little fermented, more like crab apple wine?

Birding in a Florida salt marsh

What a pleasant surprise to find such a rich and interesting wildlife refuge just an hour north of Cape Canaveral — Blackpoint Drive, a 7 mile road along dikes in a salt marsh that is part of the Merritt Island National Wildlife Refuge.

Blackpoint Drive wildlife refuge, Titusville FL

A typical scene along the dike roads of mangroves and pools in the salt marsh.

Here’s how the Fish and Wildlife Service describe this unique area.

Imagine a broad, flat expanse of salt marsh stretching from where your car is parked to the Indian River, a distance of about 1 mile. The only obstruction is an occasional hammock of palms or a mangrove-rimmed pond, and behind you, on higher ground, slash pines. Marsh streams gracefully wind through the marsh and provide a thoroughfare for microscopic plants and animals, shellfish and fish. Egrets and herons are poised along the stream edge, like spearfishermen patiently awaiting a meal. Secretively, sparrows search for insects in the chest-high grass. Occasionally, tides aided by a strong wind flood the marsh, and on the ebb, nutrient-laden waters are exported to the river. The marsh and river are one.

Blackpoint Drive wildlife refuge, Titusville FL

An island of palmetto on higher ground stands behind the sea of grass in the salt marsh.

Although we were visiting before the big influx of winter migrants arrived, there was still plenty to see, which is why a 7 mile drive took us more than 3 hours. Butterflies, lizards, lots of birds, alligators, and even a errant manatee that wasn’t supposed to be in this area of the salt marsh crossed our path.

Tri-colored Heron, Blackpoint Drive wildlife refuge, Titusville FL

Tri-colored Herons were common in the shallow pools lined by mangroves.

Tri-colored Heron, Blackpoint Drive wildlife refuge, Titusville FL

This one was pretty tame, and walked right up to us.

Greater Yellowlegs, Blackpoint Drive wildlife refuge, Titusville FL

Greater Yellowlegs foraged in the shallow mudflats.

Blackpoint Drive wildlife refuge, Titusville FL

A few flocks of small dabbling ducks floated in the deeper pools, but quickly took cover in the mangroves when they spotted us.

Alligator, Blackpoint Drive wildlife refuge, Titusville FL

Floating in some of those same deep pools were alligators of various sizes, from small like this one to very large.

Little Blue Heron, Blackpoint Drive wildlife refuge, Titusville FL

A solitary Little Blue Heron stalked its prey.

Great Blue Heron, Blackpoint Drive wildlife refuge, Titusville FL

Mangroves make useful perching spots for both Great Blue Herons and Great (White) Egrets.

Yellow-dumped Warbler, Blackpoint Drive wildlife refuge, Titusville FL

Yellowthroat and Yellow-rumpled Warblers were frequently seen foraging in the low bushes and mangroves along the water’s edge.

Juvenile and adult Common Moorhens, Blackpoint Drive wildlife refuge, Titusville FL

Common Moorhens must have raised their brood in these pools lined by mangroves. This juvenile bird is flanked by two adults in the background.

Manatee, Blackpoint Drive wildlife refuge, Titusville FL

The manatee was swimming along the edge of a small stream, squeezing itself through culverts that connected waterways. Apparently they are restricted from this area because they get stuck and have to be rescued and removed by wildlife biologists.

Black Vultures, Blackpoint Drive wildlife refuge visitor center

We found Black Vultures resting in the shade on the lawn of the visitor center 2 miles up the road from the wildlife refuge. It was close to 90 degrees and very humid, so no wonder they took refuge here.

What an amazing area, the last remnant of the natural salt marshes that probably lined the eastern coast of Florida before it was extensively developed. Not only is it a haven for wildlife, but it’s a natural barrier to storm surge and salt water intrusion inland.