Friday, July 31, 2015

Loggerhead Shrike

On Wednesday, 29 July, John Holden and I drove up to the 180th Street Marsh in nearby Dakota County. Our goal was to photograph one of the breeding Loggerhead Shrikes reported off and on all summer. Previously, we made unsuccessful forays to the area—today we found this juvenal bird immediately upon our arrival, about a quarter mile west of the marsh.

Here in Minnesota, the Loggerhead Shrike is a rare, local, summer resident. Across all of North America, populations of these shrikes have declined due to the spraying of biocides, changes in agricultural practices, and competition form other bird species. Northern populations are migratory, replaced in winter by Northern Shrikes. One reason for this migratory behavior may be the Loggerhead’s reliance on an invertebrate diet.  Although varying regionally, invertebrates usually make up about 72% of what they eat. The remainder consists of vertebrates like small mammals and birds, reptiles and amphibians (Yosef 1996).

Thursday, July 30, 2015

Barred Owl

After leaving Venice, on 25 March, Erika and I revisited one of our favorite Florida locations—the National Audubon Society’s Corkscrew Swamp Sanctuary. Admission cost is reduced for Audubon members who remember to bring their membership cards. This visit was our third, and we saw different things each time.

One highlight of this year’s visit was this fledgling Barred Owl. Nests are found in mature forests with good understory. Nest trees are often found near water, and usually in areas with high prey densities. Eggs are usually laid from March through April, and as early as December. The young fledge at about five weeks, and the parents feed them for four to five months (Mazur and James 2000).

Wednesday, July 29, 2015

Venice Rookery

On 24 March, Erika and I spent the night in Venice, Florida. The next day we were close to our goal of Sanibel Island, and so found ourselves with a bit of time to explore. We found our first destination by looking for nearby hotspots in BirdsEye, the phone app that serves as a birding “Geiger Counter.” We found a rookery a short distance from our hotel run by the Venice Area Audubon Society. We recognized our destination by the groups of birders with long camera lenses.

We did not see anything too spectacular at this urban rookery, but we were able to take some nice photographs. The Great Blue Heron in the first photo, according to Vennesland and Butler (2011) “is one of the most widespread and adaptable wading birds in North America.” Anhingas, the bird in the second photo, are common tropical birds that, in the United States, inhabit southeastern coastal areas. Anhingas are sometimes called Snake Birds because of their long, snake-like necks, or Water Turkeys, due to their turkey-like tails.

I have previously posted other information on both these species, Great Blue Heron and Anhinga. By the way, if you find missing photos in your exploration of my blog, please let me know. Such was the case with my linked heron photo. I suspect interference from I replaced the heron photo for the link in this paragraph.

Tuesday, July 28, 2015

Black-crowned Night-Heron

During our March visit to Sarasota, Florida’s Botanical Gardens, we did see a few interesting birds and flowers. I suspect the Black-crowned Night-Heron in the first photo has molted out of its juvenal and into its adult-like, second-year plumage. Note the dark adult feathers against its brownish back. I am not sure how to explain the yellowish underparts. Is this color a photographic artifact? Or a reflection off the water? The photo was taken during mid-day, so the light should not have been tricky.

The botanical gardens did not do a fantastic job of labeling their plants, niether in reality or in their web site. I am not sure of the identity of the orchid in the second photo. Even the volunteer docent sitting under the tree upon which the orchid grew could offer any help.

Sunday, July 26, 2015

Brown Anole

This lizard is a Brown Anole in Florida’s Sarasota Botanical Gardens, This reptile is native to Cuba and the Bahamas, but is now an invasive species in the southern United States. Many are escaped pets. The species is found in Florida, Georgia, Texas, southern California, and Hawaii. Brown Anoles eat almost anything they can catch and have high reproductive rates. They out-compete native lizards, such as Green Anoles, which have been forced into treetops (Wekipedia).

Friday, July 24, 2015

River Otter

I almost forgot to tell you that I saw a family of River Otters last March at St. Marks National Wildlife Refuge in the Florida panhandle. I happened to look up from chasing dragonflies when this adult led  four young down the shoreline. As I wrote last October, River Otters are found across North America, but populations have suffered from environmental destruction, pollution, and hunting.

Otters breed in burrows and generally give birth to up to six young. Otters are adept swimmers—they can remain submerged for up to four minutes and swim nearly seven mph. They prefer fish, but will take many small, aquatic animals.  The adult in this photograph is probably a female, since males usually establish their own groups, with often over a dozen individuals, while females stay with their own offspring. Other unrelated individuals—unrelated adults or other young otters—may join a female and help raise her offspring (Wikipedia).

Thursday, July 23, 2015

Swainson’s Hawk

Thanks to Gerry Hoestra for alerting John Holden and me of the presence of this Swainson’s Hawk along County Highway 1, just west of Dundas, Minnesota. Gerry photographed the bird on 21 July—John and I found it on the morning of Wednesday, 22 July. This species is considered to be uncommon in Rice County in the summer. Swainson’s Hawks breed across midwestern North America, from southern Canada to Northern Mexico. Southern Minnesota is the far eastern extent of their range. After breeding, they embark on a migration of over 6000 miles to wintering areas in the pampas of Argentina. When breeding, this hawk consumes rodents, rabbits, and reptiles; in the winter and during migration, it is almost entirely insectivorous, eating mainly grasshoppers.

While we were photographing this bird, it stretched its neck and proceeded to silently gape. I suspect this behavior is an example of pellet-casting, typical of hawks of owls. According to Bechard et al. (2010), Swainson’s Hawks expel one pellet per day. I did not, however, see a pellet drop.

Wednesday, July 22, 2015

Eastern Pondhawk

At the Marie Selby Botanical Gardens in Sarasota, Florida, we once again identified Eastern Pondhawks. In a recent post I wrote about this abundant species. In the United States, Eastern Pondhawks are found throughout the eastern states, west to easternmost New Mexico and Colorado. A similar species, the Western Pondhawk, is found from there across to California and north to the Pacific Northwest. In the small area of overlap, intermediate forms exist. This apparent hybridization makes some scientists think these two populations are actually subspecies, and they call the combined populations Common Pondhawks. I will show you a photo of a Western Pondhawk in a future post.

Tuesday, July 21, 2015

Blue Dasher

Blue Dashers were also an abundant species that we often encountered during our March Florida journey. We found them at the Sarasota Botanical Gardens on 24 March. The first two photos are of an individual landing on a weed on 23 March at St. Marks National Wildlife Refuge in the Florida Panhandle.  The bottom photo is of an immature male at Harns Marsh, near Corkscrew Swamp, on 25 March.

Blue Dashers may be migratory in parts of their range, but are generally abundant across most of the United States, and are also found south all the way into Central America. They are absent from the northern Rocky Mountains and northwestern Great Plains. I have encountered them both in urban gardens and more wild areas, usually with nearby cattail habitats.

Monday, July 20, 2015

Eastern Amberwing

As we continued our travels in Florida last March, Erika and I went out of our way to visit the Marie Selby Botanical Gardens in Sarasota. We had read that these gardens were a jewel tucked away within the city. The gardens were nice, but not large enough to attract a great diversity of birds. We did see a few dragonflies, although none were new to us. We were pleased that our University of Minnesota Landscape Arboretum memberships allowed us free entry.

Among the dragonflies we saw were these male Eastern Amberwings. I was impressed by how much the amberwings looked like small, golden wasps. As I have previously blogged, this resemblance may be the result of Batesian Mimicry, wherein harmless species evolve to look like poisonous ones and thereby gain some respect from potential predators.

Sunday, July 19, 2015

Atamasco Lily

Last March at St. Marks National Wildlife Refuge on the Florida Panhandle, Erika and I were impressed by the Atamasco (or Rain) Lilies. These colony-forming wildflowers grew along the roadsides. The flower and grass-like leaves grow from an onion-like bulb. They are native to, and common in, the southeast, and, along with wet roadsides, favor damp woodlands. The leaves and bulbs of this plant are poisonous (Wildflowers of Alabama). Zephyrus, the generic name, alludes to Zephryus, who "in Greek myth [was] the west wind and husband of Chloris, goddess of flowers” ( Atamasco is a Native American word for the red stain that often is seen on the flowers.

Friday, July 17, 2015

White-faced vs. Glossy Ibis

I mistakenly thought that the ranges of Glossy and White-faced ibis overlap just in southern Louisiana, with the Glossy found east and the White-faced breeding west. In fact, the Glossy Ibis nests west well into the Texas Gulf Coast. White-faced Ibis are expected from Alabama on west, thus producing a relatively wide area of overlap. In this area, however, the two species do not interbreed, even were they occur in mixed colonies.

Erika and I saw both species in the same flock in the Florida Panhandle, at St. Marks National Wildlife Refuge.  One of the great advantages of birding with the eBird mobile app is that it alerts you when you try to report rare birds to eBird. In the field, this means I have the opportunity to know when take photos of the birds that I might not know are unexpected in an unfamiliar region. My cell phone alerted me that White-faced Ibis were unlikely in Florida.

The bird in the top photo is clearly a White-faced Ibis.  Note the red facial skin and, if you enlarge the photo, red eye. The bottom bird is a Glossy Ibis.  Note the blue facial feathers and dark eye. Thus, I was able to submit the photograph of the White-faced Ibis when I submitted my list to eBird.

Wednesday, July 15, 2015

Slender Baskettail

On 23 March 2015, we stopped at St. Marks National Wildlife Refuge in the Florida panhandle. We had visited in February 2011. In 2015 we saw many fewer birds, perhaps due to the later date. But we were amazed to find swarms of dragonflies. Most appeared to be Slender Baskettails, although, to my disappointment, this identification was not vetted by Odonata Central. I believe my identification is correct, and for the following reasons. Most individuals, like in the first photo, had little or no dark markings at the base of the hind wing. Note the constricted apex of the abdomen on the baskettal in the second photo. More significantly, the yellow lateral spots on the third abdominal segment are not square, but somewhat elongated and tapering.  Finally, the cerci, the extensions off the end of the abdomen, are relatively long and slender.                 
Some of the dragonflies may have been Common Baskettails. The two species are known to occur together. The top dragonfly in the last photo may be a Common Baskettail. The dark marks at the base of the hind wings are more extensive than in the other two and the abdomen may be a bit more stocky.

Tuesday, July 14, 2015

Palamedes Swallowtail

Erika and I spent the night of 22 March 2015 in Daphne, Alabama. Upon our arrival at our motel, I took a short stroll, but saw little of interest—an ubiquitous Eastern Pondhawk (a female in the photo below) and a Yellow-rumped Warbler—before I discovered a Palamedes Swallowtail, a new species for me. This butterfly is common in the American southeast. Typical of swallowtails, Palamedes visit flowers and mud. The larvae feed on laurels. Adults fly all year in southern Florida, but from March through fall elsewhere in the south.

Sunday, July 12, 2015

Eastern Pondhawk / Orange Bluet

On 20 March 1015 at Louisiana's Avery Island gardens, Erika and I saw our first dragonflies of the year—if you don’t count an unidentified dragonfly being eaten by a Great-tailed Grackle near Dallas and a dead Common Green Darner along the Texas coast. Our first Odonata was a the male Orange Bluet, a rather striking damselfly known by its orange10th abdominal segment and wide, orange thoracic stripe. Orange Bluets fly in Louisiana from February through November. They usually hunt in the late afternoon, causing them to be missed by midday censuses. The species is found across much of eastern North America, west across the Great Plains, and south into Mexico. I have seen them at various locations in Minnesota.
We also listed Eastern Pondhawks. Judging by the numbers we saw almost everywhere we subsequently visited in the South, pondhawk populations must be huge. They are found across eastern North American and south through Costa Rica. We have often seen this species in MinnesotaPaulson (2011) describes them as being “superabundant” and “voracious.” As with the bluet, Louisiana pondhawks fly from February through November. In Florida, we took the bottom photograph of a male Eastern Pondhawk hitching a ride on an alligator’s back.

Friday, July 10, 2015

Red-cockaded Woodpecker

As John Holden and I attempted to photograph nuthatches at Big Branch Marsh National Wildlife Refuge near Covington, Louisiana on 21 March, Erika came running back down the Boy Scout Trail. She and Kathy had discovered several Red-cockaded Woodpeckers about a quarter mile further up the road.

Red-cockaded woodpeckers are found from eastern Texas to southern Virginia, but their range is quite fragmented. They require old-growth Long-leaf Pine, which has been lumbered, converted to Slash Pine, and otherwise destroyed by human and environmental factors (such as bark beetle infestations and hurricanes). As a result, only about 10,000 adults survive across their range. These birds breed in family groups, called clans, near clusters of older, but living, trees. Breeding pairs are often assisted by offspring, almost always males, hatched in previous years (Jackson 1994; Birds of the World—Alive; Costa 2002).

Red-cockaded are one of our most studied woodpeckers. The species is nonmigratory, and nesting colonies are usually known to local birders. Indeed, most of these woodpeckers persist in scientific study areas, often on Federal land. Look closely at the bottom photograph and notice that the bird is adorned with at least two leg bands.

Thursday, July 9, 2015

Brown-headed Nuthatch

On 21 March we searched for Brown-headed Nuthatches and Red-cockaded Woodpeckers near Covington, Louisiana. The night before we hooked up with our Northfield friends, John and Kathy Holden. We headed out to nearby Big Branch Marsh National Wildlife Refuge, knowing from fellow birders in Baton Rouge that the refuge harbors both birds.

Brown-headed Nuthatches are found only in southeastern pine forests, where the species is common. Kathy and Erika were happy to escape their slow-walking husbands and power-walked down the Boy Scout Trail, which led through Long-leaf Pine—perfect habitat for our target species. These nuthatchs' preference for mature forests make this an indicator species for the health of the forests they inhabit (Slater et al. 2013).

John and I were  almost immediately greeted by a large flock of nuthatches. The only problem for me, the photographer, was that the birds scolded us from high in the trees and did not come close to check us out. Later we found the bird in this photograph. It stuck around low in a lone pine in a nearby marsh. I suspect it had a nearby nest. The species is known to nest lower in the trees than in the canopy where it forages.

Brown-headed Nuthatches are remarkable because of their using tools and cooperatively breeding. They often use pine bark chips to pry off other pieces of bark. Up to a third of breeding pairs enjoy helpers at their nests. These helpers are generally related to the breeding pair and “assist with territorial defense, nest construction (excavating and nest-building), nest sanitation, and feeding of nestlings, fledglings, and the female at the nest” (Slater et al. 2013).

Tuesday, July 7, 2015

American Avocet

Late last March, we raced across southern Louisiana so that we might have time to explore the Avery Island gardens. Along the way we came upon this flock of American Avocets. A quick guess suggests that only about 15% of these birds retain their winter (basic) plumage, with little or no trace of orange on the heads or breasts. The others are well on the way to their spectacular breeding (alternate) plumage. This percentage of winter-plumaged birds may be a bit higher than expected, as Ackerman et al. (2013) report almost 90% should be in full breeding plumage by early March.

Avocet sexes are identified by the bill shape—shorter and more strongly up-curved on the female. Unfortunately, all but one of these birds (the second to the left) are sleeping with their bills tucked under their scapulars. Without bills to compare, separating avocet sexes can be a challenge.

Sunday, July 5, 2015

Bonaparte’s Gull

After leaving Texas in March, we raced across our old stomping grounds in southern Louisiana. Our goal this day was Covington, Louisiana, and, along the way, we wished to visit Avery Island, famous for their gardens and for being the home of Tabasco Sauce. The McIlhenny family subsidized many of our graduate expeditions to Peru during our years as graduate students at LSU.
Our coastal route required several short ferry crossings. At one of these ferries, we were followed by a small flock of Bonaparte’s Gulls. These birds are among the smallest of North American gulls. Despite their being common, I had only once previously photographed one. Small fish make up the bulk of their diet, and here they were attracted to fish and small invertebrates caught in the ferry’s wake. These are basic (winter) plumaged birds. Later they will sport black heads. In all plumages, they can be recognized by the long, white triangles on their outer wings.

Saturday, July 4, 2015

Prince Baskettail

Scott King alerted me to the presence of Prince Baskettails at Carleton College’s Lyman Lakes. After one unsuccessful search, I found these two, a male and a female I think, near the bridge separating the two lakes. The dragonflies’ presence here was curious, since Barn Swallows, with a definite appetite for dragonflies, bred under the bridge. The swallow ate an Eastern Forktail perched nearby.

These baskettails never perched, but returned repeatedly to the water along the bridge. Indeed, Prince Baskettails may seldom land—spending most of the day in flight (Mead 2009). They fly under six feet above the water, and, when they do land, it is often in tree tops (Paulson 2011). Paulson also warns that Prince Baskettails, which range across eastern North America,  are much more heavily spotted on the wings in the south and may be a distinct species.

Friday, July 3, 2015

Barn Swallow with Forktail

At the bridge separating the two Lyman Lakes on Carleton College’s campus, I photographed this Barn Swallow with an Eastern Forktail grasped between its mandibles.  Look closely at the damselfly’s blue tail tip—it has a black notch on the underside, a field mark of the forktail. Another swallow, which appeared to be the mate, perched on the same branch. I was standing on the bridge, and my guess was that the swallows were waiting for me to move before feeding the damselfly to their young under the bridge.

Although flying insects make up almost all of Barn Swallow diets (99.8%), Damselflies are actually not their preferred prey. Flies are their preferred prey (about 40%), along with beetles (15%), hymenoptera (13%) , with odonata coming in a distant third at 4%; other flying insects make up the remainder of their favored diet (Brown and Brown 1999).

Thursday, July 2, 2015

Great Egret

Great Egrets breed around the world—North and South America, Europe, Asia, China, Australia, New Zealand and Africa. The fact that this species was decimated during the plume-hunting era is hard to remember. American populations recovered only after changes in women’s millinery habits and the passage of the Migratory Bird Treaty Act of 1913. (To think that some of our politicians today would gladly gut this act.)
Last March, Erika and I often saw Great Egrets as we drove up the Texas, Louisiana, and Florida coasts. The bird in the top photo was photographed at Avery Island, Louisiana. The egret in the second photo was displaying on a windy day at High Island, Texas. This behavior is called a “Bow Display.”  The head is lowered while the bird grasps a branch—a male advertising display and also perfomed by paired egrets before their first copulation (Mccrimmon et al. 2001).

Wednesday, July 1, 2015

Rainbow Bluet

On Sunday, 28 June, I explored Lyman Lakes, small bodies of water on the Carleton College campus here in Northfield. A good number of Odonata flew about the lakes, and I took over fifty photos, including this one of a Rainbow Bluet. I had not seen this damselfly since 2012, when I enjoyed my first encounter in the nearby St. Olaf College wild area. Male Rainbow Bluets, with their orange face, greenish thorax, and blue on the abdomens are unmistakable. Note the reddish-orange dots at the wing tips. Both of the Rainbow Bluets I have seen have been perched on pond-side vegetation. Females sometimes submerge to lay their eggs inside aquatic plant stems (Dubois). Dubois’s excellent guide, Damselflies of the North Woods, is out of print, but I understand that a new edition is planned.