Thursday, March 31, 2011

Lake Mattamuskeet

Our final birding destination during our February 2011 trip was pilgrimage to Mattamuskeet National Wildlife Refuge on the North Carolina mainland behind the Outer Banks. Mattamuskeet was one of my first exotic birding destinations.  John Trott took us seventh graders on a birding trip there in the fall of 1960.  Fall is the best time to visit the refuge.  Waterfowl numbers had already peaked when we visited.  We enjoyed Tundra Swans, possibly the same individuals we had seen migrating near Brownsville, Minnesota, last fall. (An American Coot laughs at us in the foreground.)

We also listed a few other ducks, like the pintail pair below.  Pintails are capable of phenomenal migrations.  When I wrote Birds of South Dakota (with David Swanson and Jeff Palmer), I included banding records from that state.  Pintails banded in South Dakota have been recovered all across North and Central America. Two pintails banded in South Dakota were later recovered in the Midway Islands in the middle of the Pacific Ocean (one banded on 21 June 1955, recovered on 21 October 1955, the other banded on 20 June 1955, recovered on 1 September 1955)!  Another Pintail was banded on 31 August 1955 was recovered in Russian Asia 12 May 1982.

Wednesday, March 30, 2011

Gopher Tortoise

The city park north of New Smyrna Beach, Florida, is another location we revisited on our return journey. A two-mile boardwalk protects dunes from being trampled by joggers and dog-walkers.  We found several Gopher Tortoises guarding their burrows.  (We did not see them in 2010.) 

These terrestrial turtles are found in Florida and southern areas of Georgia, South Carolina, Mississippi, Alabama, and  eastern Louisiana. The burrow's temperature determines the tortoise's sex--over 85 degrees F, produce females, under results in males. Gopher Tortoises are classified as Threatened Species in Florida.  In Florida, habitat destruction is the prime threat--just look at the condos and hotels ringing the coastline.  Tortoises have also been killed for food or by people trying to eradicate the rattlesnakes that often share their burrows. You can learn more about Gopher Tortoises at gophertortoise.com, (where much of this information was gleaned).

Like the National Seashore adjacent to Merritt Island National Wildlife Refuge, we were surprised by the crowds at the beach. This year the beach looked more like a parking lot, so dense were the cars parked above the high water mark.  No place for birding.  Between two parked cars, however, a small flock of Snowy Egrets allowed me exceptionally close approach.  I never did flush them.

Tuesday, March 29, 2011

Red-spotted Purple intergrade

As I continue my digital butterfly search about which I previously blogged, I came upon this photo taken on 25 June 2007 on one of Erika's garden hostas in Northfield.  The butterfly appears to be an intergrade between a White Admiral and a Red-spotted Purple.  The Canadian admiral barely trespasses into the northern United States.  The purple is found in the eastern US and in Mexico.  The two butterflies have different habitats--the White Admiral is more restricted to forests, whereas the Red-spotted Purple prefers open, scrubby woods and forest edges (Klots).  My butterfly was along the forest edge.

Despite being quite different in appearance, where their ranges overlap (in Minnesota, Michigan, and New England), you encounter intergrades.  The admiral shows broad white wing stripes; the purple lacks the stripes and is purple and blue.  Klots (A Field Guide to the Butterflies) and Marrone (Field Guide to Butterflies of South Dakota) show intergrades with a lot of white on the upper wing. The intergrade shown in Kaufman (Butterflies of North America) looks similar the butterfly in my photo. Once considered to be two separate species, this hybridization forced lepidopterists to conclude that we are dealing with one polymorphic species.

Monday, March 28, 2011

Merritt Island NWR 2

Two common birds at the Merritt Island National Wildlife Refuge (Florida) include the Boat-tailed Grackle above and the Laughing Gull below.  This male grackle did not seem to be a rubber-consuming pest like the Black Vultures about which I recently blogged.  Rather this vain male perched on window wipers and appeared to be displaying towards his reflection on the windshield.  You can see the reflection in the photo.
Laughing Gulls are abundant birds of the Gulf and Atlantic coasts of North America.  This photo is my first of this species in breeding plumage.  The black head probably serves a territorial function.  In other black-headed gulls, breeding pairs face away from each other, so as not to be repulsed by the black head.  Young and winter bird, like this bird wintering in Texas, have much reduced black on their heads, resulting in more cohesive flocks.

Sunday, March 27, 2011

Merritt Island NWR

We returned from our Florida trip by way of Washington DC.  We took a relatively leisurely route, which included some nonbirding destinations.  Our first stop was the Merritt Island National Wildlife Refuge, just east of Titusville (and just north of Cape Canaveral--the refuge is closed on shuttle launch days). 

Unlike our 2010 visit, we had no trouble finding Florida Jays, a species endemic to the state.  The jays were common just north of the entryway to the National Seashore.  We stopped at the seashore, but were disappointed by the crowds there.  With near record low temperatures last year, we had the beach  to ourselves.

Another highlight of the refuge is the auto wildlife drive.  We saw many birds there, often with close views, such as the Savannah Sparrow below.  Also noted along the trail were a Clapper Rail and wild boars.  Early morning visits are definitely advised, since the refuge becomes crowded as the day progresses.

Friday, March 25, 2011

Chasing Digital Butterflies


I am reading Mariposa Road by Robert Pyle.  The book is inspired by Kenn Kaufman's Kingbird Highway, in which teen-aged Kenn Kaufman attempts to break the record for birds seen in a year--except the the Mariposa tome is about Pyle's attempt to see a record number butterflies in a year.  The book is about a third butterfly list, a third autobiography, and a third travel essay.  I enjoy all three genres.

To to really like Mariposa Road, I suspect you foremost need a latent interest in butterflies. My blog readers know that I possess this trait.  Pyle is also a birder, and like birders recounting great birding days, he delights in stories of butterflies seen right here but last year.  (In fact, in the first 10% of the book he records more birds than butterflies--he only sees about eight butterfly species! Pyle writes, "If you are a butterflier, it's best to be a birder too, since that way you can almost always occupy yourself.")  Despite Pyle's relatively erudite writing style--a gimlet, for example, is really a strong gin cocktail, not a piercing stare from the Border Patrol--I find myself inspired to search more diligently for butterflies. As I read Mariposa Road, I looked up the butterflies Pyle sees in the Kaufman butterfly book.

Winter/early spring in Minnesota might seem a poor season to kindle an interest in lepidoptery.  But even if I have seldom identified them, I have taken photographs of the butterflies that have crossed my path (and remained still for inordinate amounts of time).  So I have begun a search for digital images of butterflies among the pile of files stored on my external hard-drives. Now that I own a copy of Kaufman's Butterflies of North America, identification is more assured.

My first digital discovery is this image of a Bog Fritillary taken a couple of summers ago in Minnesota's Boundary Waters.  According to Kaufman, the second row of black-edged, white spots on the hind wing cinch identification.  This Canadian denizen barely dips into the United States, but found some sustenance on our plastic camp-ware.  I am, however, just a beginning butterflier.  Hap Huber writes that this critter looks more like an Atlantis Fritillary, another northern species.  He points out that the back wing of my butterfly is badly damaged.  Furthermore, the black-rimmed spots should be in a neater row if my identification was correct.  I bow to his greater experience!

Thursday, March 24, 2011

Snail Kite

While birding in Tabasco, Mexico, in 1964 I took the lower photograph of a male Snail Kite.  This February, in the Everglades National Park, Erika and I followed directions in A Birder's Guide to Florida. We scoped out the marsh behind the abandoned airboat port just west of the Casino next to Shark Valley.  Amazingly, although from quite a distance, a female Snail Kite floated in the air, once or twice diving to the ground.

This raptor is extremely specialized.  In Florida it feeds  almost only on the Florida Applesnail, the largest freshwater gastropod in the country.  Look closely at the left foot of the bird in the photo above--it is carrying an applesnail.  These snails grow to about 60 mm.  The photo below shows the hooked bill this bird uses as a snail-extractor.  Snail Kites tend to be nomadic in south Florida, their presence depending on snail populations and water levels.   Since this kite is also found from Mexico to northern Argentina and the Florida Applesnail is only found in Florida and Cuba, other Snail Kites must specialize on other gastropods.

Notice the fuzzy image of a second bird in the first photo.  At the time, I was too busy taking photos of the Snail Kite to really notice the second bird.  This bird appears to be a Wurdemann's Heron, the hybrid between the Great White and Great Blue Heron.  This intergrade has a Great Blue-colored body and a white head and neck.  We never saw another during our travels.

Wednesday, March 23, 2011

Black Vultures and Vinyl

On our early morning arrival at the Everglades National Park's Anhinga Trail, a sign greeted us with a warning that vultures may cause damage to parked cars.  Mysterious, we thought, but a mystery soon solved as Black Vultures began landing on the cars.  The vultures appeared to be scavenging for bugs, either window-killed or dropping from overhanging trees.  Many visitors to the park, however, warn that Black Vultures, much like New Zealand Keas, destroy rubber window sealant and window wipers. The national Park has been sued for this damage--hence the warning signs.  The attraction of rubber and vinyl for Black Vultures remains unexplained. Turkey Vultures, like the one in the photo below, kept to the skies, likely on the lookout for more traditional carrion.

Tuesday, March 22, 2011

Exotic Lizard Invasion

Annually as many as 8000 Green Iguanas are imported into the United States through the pet trade from Central and South America. A Green Iguana Society even exists (and advises to remain calm when your pet bites you--note the teeth in the photo below). Iguanas also stowaway on fruit shipments from the tropics. Docile vegetarians, they sound like great pets.  But they often outgrow their owner's ability to house, care, and feed them.  Many die--they do not fare well being fed meat (or iceberg lettuce)--and others escape captivity or are liberated to the wild.  In south Florida, they out compete native vegetarians and cause considerable damage to local flora. Similar invasions have occurred in south Texas and Hawaii. New York and Hawaii forbid ownership of Green Iguanas. We encountered them in two state parks in the Florida Keys.

Monday, March 21, 2011

Roseate Spoonbill

Roseate Spoonbills attract birders to both the Texas and Florida coasts.  The oddly shaped bill is swished through the muddy water for invertebrates.  Many prey items may be kicked up as the bird walks through swampy water.  Judging by the well-vascularized bill visible in the the photo above, I was not surprised to discover that spoonbills are tactile feeders--snapping their bills closed when they feel prey between their mandibles (Dumas 2000).
The birds in the first two photos are juveniles, as indicated by their feathered heads.  Adult birds, like the spoonbill below, become bald.  The head skin becomes pale greenish blue. Spoonbills in the United States were nearly extirpated by the 1940s.  Now numbers are increasing, but the species is of special concern in Florida and Louisiana. Texas, Louisiana, and South American populations appear to be disjunct from those of Florida and the Caribbean.  If genetic isolation continues, one might predict isolated populations accumulating genetic differences leading to speciation.  This situation, however, is not well investigated (Dumas 2000).
The top two photos were taken in the Merritt Island National Wildlife refuge just east of Titusville, Florida, and the bottom ibis fed near Flamingo, in the Everglades National Park.

Sunday, March 20, 2011

Ruddy Daggerwing

This Ruddy Daggerwing is one of the highlights of our stroll through Corkscrew Swamp Sanctuary near Naples, Florida.  This large butterfly warmed itself in the morning sunlight.  The species is found along both coasts of Mexico and in southern Florida, where it flies all year, it inhabits hardwood hammocks.  In the Midwest summer, the species strays north to Nebraska.  The larva are fond of fig leaves, the adults are attracted to flowers and rotting fruit.

A butterfly that escaped my lens is the Zebra Heliconian, a long-winged, black-and-yellow striped beauty that feeds on passion vines.   Alligators be damned, next time I see one I will have to chase after it more fervently!

Friday, March 18, 2011

Corkscrew Herons

The Corkscrew Swamp Sanctuary, run by the National Audubon Society, is a must-see attraction for  visiting birders.  The preserve, located a few miles west of Naples, Florida, contains a two-mile boardwalk through a pristine cypress swamp.  A reduced entrance fee is charged for Audubon members. Most birds allow close approach, like the Little Blue Heron above. Audubon volunteers man the walkway and can answer some of the questions you may ask.  Images of birds, like the Great Egret below, even reflect from the swamp waters. I have read that no two trips to Corkscrew are similar, and Erika and I found this statement to be true.  Visits in 2010 and this year yielded different bird lists.

Thursday, March 17, 2011

Lapland Longspur

On 16 March 2011, I got my first photograph of a Lapland Longspur.  This milestone is surprising because Lapland Longspurs are among the most common birds in North America, and is especially abundant in the winter in the mid-west.  Some wintering flocks have been estimated to contain four million birds! One problem is that they breed in the arctic and spend the winter camouflaged in fields.  Unless snowy weather forces longpsurs to roadsides, one can have trouble finding these often wary birds.  Near Northfield, Minnesota, Gene B. and I found several Lapland Lonspurs in a mixed flock that contained a half-dozen Horned Lakes and a single Snow Bunting.
This individual is acquiring its striking breeding plumage, molting from its drab winter colors. Lapland Longspurs can be difficult to identify.  An unwary birder might decide this bird is a Chestnut-collared Longspur.  After all, this bird has a chestnut collar and a striking black and white facial pattern.   In all plumages, the chestnut-edged greater coverts are an excellent field mark (very apparent in the first photo).  Another good field mark is this bird's streaky flanks, streaks lacking in other longspurs.  Finally, the dark breast band, visible in the photo below, is restricted to the upper breast and contrasts with the white belly.
In most current field guides, taxonomically longspurs are placed among the sparrows.  After a decade of genetic studies, ornithologists have decided that longspurs and sparrows are not closely related.  Lonspurs now occur after waxwings and before warblers.  They are no longer placed in the sparrow family Emberizidae. They now reside their own family, Calcariidae.

Wednesday, March 16, 2011

White-fronted, Cackling, and Canada Geese

On 15 March 2011, Gene B. and I found Canada, Cackling, and White-fronted Geese in a flooded, icy field near Northfield, Minnesota. This photo shows all three species.  The Cackling Goose is the stubby-billed, small goose near the left of the photo.  Even from a distance, White-fronted Geese, often called Speckle-bellies, can be identified by their orange legs and by the white stripes that run up their sides. I previously posted about Cackling Goose identification in this blog on 12 November 2010.

Although Gene and I saw all three in the same flock, this photo was taken several years ago in Sand Lake National Wildlife Refuge near Aberdeen, South Dakota.  The birds we saw near Northfield were in bad light and quite a bit more distant. Nevertheless, a welcome sign of spring!

Tuesday, March 15, 2011

American Kestrel

Erika and I photographed a pair of Kestrels near Big Woods State Park, Minnesota, on 14 March 2011.  The day was warm at 40 degrees F and there was some snow melt--you can see that both members of the pair had wet tails.  The male was more skittish than the female, who obliged us with the closeup photo below.

American Kestrels nest in cavities.  They use either natural holes in trees or abandoned woodpecker cavities. Rock crevices and holes in buildings are also used. Kestrels readily use nest boxes, and the MN Department of Natural Resources has placed such boxes on the back of some Interstate road signs in the state. Males usually migrate before females. Females then select males. Males locate and lead females to nest cavities within their territories. The females then make the final nest selection (Smallwood and Bird 2002).

Monday, March 14, 2011

Anhinga Trail

The Anhinga Trail is a birding hotspot in the Everglades National Park.  A short boardwalk leads out from a parking lot near the beginning to the road leading to Flamingo, Florida.  Despite being crowded with tourists, birders and nonbirders alike, the Anhinga Trail birds are remarkably tame--so tame that Erika and I felt we were photographing birds in a zoo.
The first two birds are rails, the Common Moorhen (top) and the Purple Gallinule, (middle).  Both rails lack a duck's webbed toes.  The bird below is the trail's namesake, the Anhinga.

Sunday, March 13, 2011

Wood Stork

The only stork and the largest wading bird that breeds in the United States, the Wood Stork is found in the Southeast, as well as coastal Mexico, Central America and the Caribbean. Due to the degradation of the Everglades, Wood Stork populations have significantly declined since the 1960s. As south Florida populations decreased, Wood Storks are more often seen north into northern Florida and coastal South Carolina.  Breeding success has been limited in these northern areas. We found these storks along the Anhinga Trail in the Everglades National Park (top and bottom photos) and in the Merritt Island National Wildlife Refuge.  Neither area should be missed by visiting birders.

Since I photographed many Florida birds during our trip in 2010, this year I attempted to take some photos showing birds "artistic" poses.  The photo above is a result.  I purposefully centered the shot on the eye, cutting off the tip of the bill and the body.  If nothing else, you can see the origin of the Wood Stork's folk name of Ironhead or Flinthead.
Wood Storks are tactile feeders, they capture food by feeling with their bills  Although they can feed visually, tactile feeding allows them to forage in murky wetlands, without depending on sight. As you can see in the photo below, this Wood Stork is feeding with its bill completely hidden. (Much of the information in this post is gleaned from Coulter et. al 1999).

Friday, March 11, 2011

Crab-like Spiny Orb Weaver

The Crab-like Spiny Orb Weaver is certainly a small creature that deserves to have its common name capitalized.  We encountered this spider in the Key West Botanical Garden.  The species is found along woodland edges and citrus groves from the southern United States south through the Caribbean and South America.

Breeding males approach a female's web and tap out a four-beat "tune" on her web.  The female ties him down, and a lengthy copulation ensues. I assume the male survives this welcome.  Females are short lived, dying after laying egg masses in the spring.

As you can see, this spider leaves prey remains in its web.  The Crab-like Spiny Orb Weaver is not considered to be hazardous to humans. Indeed, this spider is welcomed by citrus growers, as the arachnid consumes fruit flies, as well as white flies, mosquitoes, moths, beetles, and other small flying insects.

Thursday, March 10, 2011

White Ibis

The White Ibis is a common wading bird of the southeastern United States and coasts of Mexico and Central America.  They breed in wetlands (swamps and esturaries), often favoring freshwater. When they breed in salt water they may suffer salt stress and they require additional freshwater sources for their young to develop properly.  Nevertheless, White Ibis were abundant throughout the Florida Keys. 

White Ibis tend to be nomadic, thereby taking advantage of shallow feeding areas created by lack of rainfall. We also saw them foraging in fields. In Florida, as elsewhere, this ibis is "threatened by development, pollution, and water management." Their diet is varied, but concentrates on freshwater crayfish and estuarine crabs.  Just about any aquatic and even terrestrial prey item you can think of has been consumed by White Ibis--including worms, cockroaches, fish, lizards, snakes, and even young White Ibis.

This information (and quote) are taken from Heath et. al 2009 (in The Birds of North America Online), who, however, do not mention Wonder Bread as being consumed by White Ibis.  The ibis in this photo was being fed white bread by homeless-looking people in a city park in Key West. The ibis tossed the bread up with its bill and snapped the bread out of the air.

Wednesday, March 9, 2011

White-crowned Pigeon

The White-crowned Pigeon we saw in Key West was new for my United States bird-list. We were walking to a restaurant in the middle of the city when Erika looked up and asked, "Isn't that the bird you are looking for?" For once I did not have my camera--this photo was taken with my friend Mark's cell phone! Despite returning several times to the intersection where we found it, we never saw this pigeon again.

I expected to find a White-crowned Pigeon to be a shy forest resident, not perched on electrical lines in the middle of the city.  I read with interest in Bancroft and Bowman (2001) that this species has "become habituated to humans, feeding around hotels and in suburban back yards."  This bird is an obligate frugivore, which means they only eat fruit. White-crowned Pigeons are threatened throughout their Caribbean range by habitat destruction and unregulated hunting.

Tuesday, March 8, 2011

Florida Butterflies 2

After meeting two lepidopterists at the Key West Botanical Gardens, we were able to easily identify this Fiery Skipper with the aid of their excellent butterfly field guide.  Having its back-wings more fully opened than its fore-wings indicates this butterfly is a grass skipper.  This skipper wanders north from Mexico and the southern United States.  Where weather permits, this species flies all year.  Often common, the larvae love lawn grasses.  The black, toothed margins of the hind wing is a field mark of the Fiery Skipper.
Back in Key West, Erika and I found a Gulf Fritillary, another southern species that wanders north in the summer.  The black-ringed white spots in the fore-wing are indicative of this butterfly.  They fly all year in frost-free regions. The larvae eat passion vines.

Monday, March 7, 2011

Florida Butterflies 1


Erika and I visited the Key West Botanical Garden.  We met two people who knew their butterflies the way some of us know birds.  The couple strolled through the gardens with their binoculars on the ready.  Readers of my blog will know that I often photograph butterflies, and so it was with great interest that I noted their fantastic book, the Kaufman Field Guide to Butterflies of North America. We recommend the book and look forward to using it in Minnesota this summer.

Our butterflying couple identified two species for us.  The first was the Giant Swallowtail.  It inhabits the southeast and strays towards Minnesota and New England.  In southern Florida they are out all year, gracefully gliding through the foliage.  Farmers consider this species to be a pest since the larvae feast on citrus leaves.
Later we came upon the beautiful skipper photographed below.  We ran back to our experts, telling them, "we just found the most gorgeous green and blue butterfly with a tail like a tropical hummingbird's."  The couple quickly identified it as a Long-tailed Skipper and showed us its photo in Kaufman's book. This butterfly is common along the Piedmont of the southeast, the Gulf Coast, and both Mexican coasts.  It flies all year where weather permits and is an agricultural pest, as the larvae are fond of beans and other legumes.