Thursday, February 29, 2024

Yet Another Leap Year!

Lately, I have been thinking about Anurans—frogs and toads.  There are a little under 100 species in the U.S., but that’s not so many that enthusiastic amateur naturalists can’t become familiar with the most common ones in their locales in a short time.  For comparison, there are several hundred species of birds in the U.S., many of which have different plumages for different ages, sexes, and seasons, as well as multiple calls and songs for different purposes.  That’s not to say that frogs and toads show no intraspecies variation.  However, the degree of variation is less overwhelming, and, again, it’s easier to learn to identify 10-30 or so species—about the number that you could reasonably expect to find in any given region of the country, I think—than it is to learn upwards of 200 species of birds that occur regularly in the state where you live.  

How do you begin learning about frogs and toads?  Well, these days, there are several useful online resources that can help you.  I happen to like the U.S. Geological Survey page, which allows you to see the species lists for all of the eastern states (unfortunately, western states haven’t been added yet) and listen to recordings.  The Association of Zoos and Aquariums is another great site, and contains links for FrogWatch USA as well as information about amphibian conservation.  If you are interested in learning even more about amphibian identification, search the databases of Macaulay Library and AmphibiaWeb.  There are also plenty of good field guides that help with visual and/or aural identification.  When I was a child, I enjoyed listening to the cassette tape that, along with a short booklet, comprised A Field Guide to Mississippi Frog Songs.  This explains why I knew several frog sounds long before I became interested in birds.  

No matter what sources you use, though, keep in mind that there is no substitute for hearing frogs and toads in their natural habitats.  If you’re frogwatching in a particularly good location, you will probably hear several frog species calling at once, so you will need to pay close attention to the differences.  Loud, overlapping choruses of frogs and toads can sometimes make it difficult to concentrate!  During the breeding seasons, singing male frogs are working hard to attract females, so they need to be as loud and persistent as possible.  Right now, in late February and early March, the main species calling in the southeastern U.S. is the spring peeper.  In January and February, spring peepers are often outnumbered by chorus frogs, which, as I’ve mentioned before, have a metallic sound to their song.  In a few weeks, I will expect to hear toads, and, by late March, gray treefrogs, green treefrogs, squirrel treefrogs, and others will have entered their breeding period.

To help get you started learning about frogs and toads during this leap year, here are some of the short articles I’ve written about Anurans in Mississippi:


Happy frogwatching!

Wednesday, January 31, 2024

Wintry Coastal Woods

Beaches, bays, and marshes come to mind most readily when I think about coastal environments.  But the Gulf Coast also boasts a variety of wooded landscapes that provide crucial habitat for many animals and serve as buffers against storms.  In the photo below, a Great Egret fishes along a wooded coastal creek in late December.  One consequence of the moist, warm regional climate is that many woodlands tend to stay green and blooming well into the winter.

Great Egret (Ardea alba)

I love the diversity of these coastal forests.  The canopy trees may be hardwoods like black gum, water oak, or live oak; pine species; or a mixture of both.  Several of these trees, like the water oak, can be found across much of the southeastern U.S., while others, such as the southern live oak, are highly representative of coastal ecosystems.

Slash pine (Pinus elliottii) is a common, fire-resistant tree in coastal woodlands.  Note also its broad patches of bark.


Water oaks (Quercus nigra) typically have smaller leaves, but these saplings were growing in to the understory, and therefore needed more leaf surface area to capture sunlight.

This is a typically enormous live oak (Quercus virginiana).  These trees grow rapidly in the first few decades of life.

The understory trees and shrubs of coastal woods are particularly interesting, since they tend to bear obvious adaptations to the ever-changing environment.  For example, there are a number of species that are evergreen and have waxy leaves: features that help to prevent desiccation and protect against the fires that were once natural, expected occurrences on the coast.  In more recent decades, prescribed burning has aided in forest recovery.

Swamp bay and wax myrtle are two of these common evergreen coastal trees (or shrubs, depending on their growth pattern).  Both species produce provide cover for animals during the winter, and their flowers and fruits can attract many birds and other wildlife.  The wax myrtle’s leaves are smoother and have wavier margins than those of the swamp bay.

Swamp bay (Persea palustris)

Wax myrtle (Morella cerifera)

A little farther inland, mountain laurel is often a surprisingly common understory plant.  It usually grows in montane forests in the northerly portions of its range, but it may be found in low-lying areas in the coastal region.  Like the swamp bay and the wax myrtle, it has thick, waxy, evergreen leaves.  While birds and insects may enjoy feeding from its flowers, it is highly toxic to most other animals.
Mountain laurel (Kalmia latifolia)

Of course, not all understory plants of the Gulf Coast have a typical tree-like growth form.  The dramatically spiky, waving fronds of the saw palmetto give panache to the forest floor.  Like other palm species, saw palmettos stay green all year.  Their berries provide food for a multitude of wildlife species.

Saw palmetto (Serenoa repens)
 
What of the non-shrub understory plants of these coastal woods?  Well, switch cane is one of the most noticeable.  This is especially true during the winter, when many of the herbaceous—or non-woody—plants have died back, and only the toughest of them, the graminoids—a group that includes grasses and sedges—are left to provide groundcover.  Canes and bamboos actually belong to the grass family, which isn’t surprising when you consider their shape and growth habits.  Being a native bamboo, switch cane commonly grows in low-lying, swampy habitats.  In other words, don’t necessarily expect to find it in urban areas!  Of course, if it does happen to be growing there, leave it be.  Native plants deserve a chance to thrive.  

Switch cane (Arundinaria tecta)

As always, there are countless other plant species that you may find in these coastal woods.  Winter along the coast doesn’t always look the way that you might expect, and there is always a lot of greenery in the woods.  As the season gradually shifts into early spring, however, watch for changes—particularly the proliferation of herbaceous plants along the ground and the blossoming of some of the trees and shrubs in the other forest layers.  It’s always nice to have an excuse to duck into a comparatively cool, shady woodland after a long walk at the beach on a sunny spring day!

Sunday, December 31, 2023

Waterfowl Identification in the Winter

This is a repeat from several years ago.  Enjoy!

Winter is here.  The landscapes are bare of the lush greenery that cloaks them in summer, and the woodland birds—woodpeckers, waxwings, warblers, and sparrows—are constantly on the search for new sources of food in their altered homes.  Hawks, too, are taking advantage of the dining opportunities that winter brings, choosing a high vantage point as they do so, riding the breezes against a gray sky reflected on the calm water of a pond or lake nearby.

On these ponds and lakes, yet another group of wintering birds can be observed: ducks!  As they float about together, feeding on plants and small aquatic animals, they are much easier to see and identify than all those look-alike warblers and sparrows.

Or are they?

The vast majority of ducks are shy and skittish, and you’re lucky if you can creep up on them without provoking them to fly.  And some of the species that form large flocks on open water, such as scaup and Redheads, are often so far away when you spot them that you’re hard-pressed to locate any distinguishing details even with the aid of a spotting scope.  Ducks circling overhead in flight can also be elusive.  With these points in mind, let’s take a look at the ducks and duck-like birds of the southeastern U.S., and their identifying traits.

The most familiar species in the family Anatidae (which encompasses all of the world’s swans, geese, and ducks) are the dabbling ducks, in the genus Anas.  Species in this group feed directly on the surface of the water or just a few inches below it, tipping themselves forward to reach aquatic vegetation.  The Mallard is one of the most abundant and widespread dabblers, and can be seen in many wetland habitats.  The males are difficult to mistake, with their glossy green heads, rich brown breasts, and yellow bills.  Females are a mottled tawny brown with orange and black bills.  Both sexes have bright purplish-blue speculums (colored patches on the secondary feathers) bordered in white.  In addition, the Mallard is a very large duck, measuring 23 inches from tail to bill.

A similar species that was formerly common but is now in decline is the American Black Duck.  Both male and female Black Ducks look like darker versions of the female Mallard, but the male Black Duck’s bill is yellow, and the female’s is grayish.  Their speculums lack the bold white borders of the Mallards’.  The Gadwall, another duck resembling the female Mallard, is slightly smaller than its relative and has drabber feathers.  Males are mottled grayish-brown, with black tails and dark-gray bills.  Females are browner, and their bills are gray on top and have dull- orange sides.  The most distinctive field mark on this species is a small white patch on the wing, which stands out even at a great distance.

Wintering flocks of Mallards and Gadwalls often contain yet another species: the American Wigeon.  This duck is about 19 inches long and has a rounder build than these other dabbling ducks.  The males and females have brownish flanks, pale gray bills, and green speculums.  The male has green ear patches and a strikingly white forehead and cap.  The female’s head is stippled and has a tinge of olive.  

The Northern Pintail, like the Mallard, is a very large duck.  Slim and long-necked, it has sharp, pointed tail feathers, especially obvious on the male, who also has a dark brown head and a white breast.  His body is mostly light gray.  The female is mottled brown all over.  These ducks have shiny, dark gray bills.

Except for sharing the same genus, the two common species of teal in the eastern U.S. are not closely related.  They are both very small ducks, however, and have green speculums.  In addition to the green speculum, the Blue-winged Teal has periwinkle-blue wing coverts.  Both the male and the female are mostly mottled grayish-brown, but the male has a white crescent in front of the eye.  The Green-winged Teal female can be told from the female Blue-winged Teal by its browner coloration.  The male Green-winged Teal’s head is rich chestnut and green, its back and flanks are gray, and its breast is buff-colored with black speckles.  Blue-winged Teal are very common during migration, but they can be a bit difficult to find in inland areas during the winter.  Green-winged Teal may not be as abundant in the spring and fall, but they winter in these areas more frequently than their counterparts.

Blue-winged Teal
A more unusual dabbling duck is the Northern Shoveler, named for its exceptionally large, spatulate bill.  With these bills, shovelers are able to strain large amounts of mud for small invertebrates.  Sometimes called “spoonbill” or “smiling Mallard”, the male shoveler has a green head, white breast, and chestnut flanks.  Females are mottled brown, but, like the males, they have glossy green speculums.

Diving ducks, genus Aythya, forage mostly below the water’s surface.  They are often seen in huge flocks, or rafts.  They have heavy bodies and relatively short wings, so, unlike dabbling ducks, they must have a running start on the water in order to fly.  If individuals in a distant group of ducks periodically disappear and then pop up again, they are diving ducks.

Some of the most well-known members of this genus, Canvasbacks are large, robust ducks.  They have long black bills and sloping profiles.  The male has a chestnut head, black breast, and white back.  The female has a brown head and neck, and a pale brownish-gray back.  The Redhead is superficially similar to the Canvasback, but it is slightly smaller and has a shorter neck, shorter bill, and lacks the sloping profile of its relative.  Males have chestnut heads, black breasts, and gray backs.  Females are warm brown all over.  The bills of both sexes are tricolored: blue-gray, white, and black.

The white, sloping backs let you know immediately that these are Canvasbacks!  Ring-billed Gulls are in the background.
Probably the most common diving duck is the Ring-necked Duck.  Actually, it might have been better to have named it the Ring-billed Duck, as the thin chestnut ring on its neck is difficult to see, but the white-ringed black bill is obvious.  The male of this species has a dark, glossy head and breast, a black back, and gray sides.  A bright white line separates the black breast from the gray flanks.  The female is brownish overall with pale cheeks and a white eye-ring.

Ring-necked Ducks
There are two species of scaup in North America: the Greater and the Lesser.  If both species are next to each other, it may be possible to see a difference in size between them, but this is not a foolproof field mark.  Better identifying features are the more rounded head shape of Greater Scaup (Lesser Scaup have a slight point at the crown) and the higher amount of white in the Greater Scaups’ wings.  A male scaup of either species will have a dark head and breast, very pale gray flanks, and a gray back.  A female is brown, with a white patch at the base of the bill.  The bill in both sexes is gray.

A group of waterfowl collectively known as Sea Ducks includes scoters, goldeneyes, and buffleheads.  Buffleheads, closely related to goldeneyes, are the only common members of this group where I live.  These tiny ducks, just 13 inches in length, have large, round heads, small bills, and bob about on open lakes.  The male’s black head has a large, white wedge-shaped patch, and his underparts are white.  The female is grayer, with a dark brown head and a white ear patch.  Another small duck that is often seen on large ponds and lakes is the Ruddy Duck, in the group Stiff-tailed Ducks.  This species has a broad bill that on the breeding male is bright blue.  In winter birds, however, the beak is gray.  These ducks have buff-colored underparts, dark brown wings and caps, and the males have white cheeks. 

Mergansers are another set of waterfowl.  The Common Merganser, a very large, mostly pale duck with a dark head and red bill, is actually uncommon to rare in the southeastern U.S. in the winter.  Our most abundant merganser is the Hooded, a medium-sized duck with a thin, serrated bill used in catching fish and crustaceans, and possessing a somewhat bizarre appearance.  The male has rufous sides, a white breast, and a fan-like crest with a large white patch in the center.  His mate is brown with a white wing patch, and a smaller tuft of brown feathers on her head.  This duck occurs in both open and wooded areas, and nests regularly in the Southeast.

The Wood Duck also breeds in the south and is sometimes seen in winter flocks with the Hooded Merganser.  Most birders are familiar with the colorful plumage of the male Wood Duck, and the subtle brown feathering and white eye-ring of the female.  When a group of Wood Ducks is disturbed, they will often fly off with distinctive oooeeek! calls. 

Swans are rare in our area, but geese are nearly always common.  The ubiquitous Canada Goose is well-known to nearly all birders.  Stocky white Snow Geese are also present, providing opportunities to search for their smaller, rarer cousin, the Ross’s Goose.  And, if you’re on the lookout for waterfowl, you may also spot Greater White-fronted Geese mingling with Canada and Snow Geese, or perhaps foraging on their own.  Their brown necks and orange bills are distinctive.

There are also duck look-alikes, such as grebes and coots, both of which have lobed, not webbed feet.  The little Pied-billed Grebe usually swims alone or in small groups.  It frequently submerges itself in the water, only to pop up again several feet from where it dived.  American Coots are very duck-like in their habits, although they are related to rails and gallinules.  Their stocky gray bodies and chicken-like white bills are noticeable even from a great distance.

When you’re out birding this winter, be sure to witness the fascinating behaviors of the ducks, geese, and other waterbirds that are taking up residence.  With their myriad forms and patterns, they bring striking color and vibrant action to our cloudy, gray landscapes.

Ring-necked Ducks and Green-winged Teal