Human Impact

The Adaptable Cattle Egret

Cattle Egret with Feral Hog at Pilant Slough, Brazos Bend State Park, Texas
In Deepest, Darkest Texas: Cattle Egret with feral hog at Pilant Slough, Brazos Bend State Park, Texas. True pigs have been in the New World for centuries due to human introduction. Cattle Egrets commonly follow cattle around Texas pastures, but this is the first time I have seen the birds shadowing prey-flushing pigs. All photos Canon EOS 7D/600mm f/4L IS (+1.4x TC).

Cattle Egrets are among my favorite waders. They are slightly sinister in appearance and behavior as they sneak and skulk around the margins of grasslands and marshes in search of invertebrate and small vertebrate prey. And judging by their large minimum approach distance they are among the most suspicious and distrustful of birds.

Given their dislike of people, it’s ironic that the rapid expansion of Cattle Egrets across the New World in the latter half of the 20th Century has been aided by human agriculture. Not long before the 20th Century the Cattle Egret was an Old World species. The first Cattle Egret was seen in the New World in 1877; in North America in 1941, and it began breeding in Florida in 1953. Today, Cattle Egrets are widely distributed across the Americas.

A Cattle Egret in Breeding Colors at Smith Oaks Rookery, High Island, Texas
Spectacular: A Cattle Egret in Breeding Colors at Smith Oaks Rookery, High Island, Texas. Natural light.

Although we think that the Cattle Egret reached the New World on its own, the widespread distribution of livestock here, particularly cattle, has has greatly facilitated the bird’s spread. Today, Cattle Egrets snapping up grasshoppers and other prey flushed by cattle (or farm implements!) is a common American sight.

So in the Americas, the Cattle Egret is not a human-introduced species. Yet, I find it hard to consider it precisely a native species (over much of its range) given its close association with domesticated livestock. The Cattle Egret exists exactly at the intersection of man and the rest of nature. It is one of those species well adapted to live in a human-influenced, agricultural landscape. And, as the human population increases with its ever-increasing appetite for meat and animal products, the Cattle Egret’s future looks bright indeed.

Mating Cattle Egrets at the Smith Oaks Rookery, High Island, Texas
Mating Cattle Egrets at the Smith Oaks Rookery, High Island, Texas. Cattle Egrets now breed in rookeries with native species such as Great Egrets, Roseate Spoonbills, Tricolored Herons, and Snowy Egrets. Natural light.

It is not the strongest or the most intelligent who will survive but those who can best manage change.—Charles Darwin 

©2014 Christopher R. Cunningham. All rights reserved. No text or images may be duplicated or distributed without permission.

Where Have All the Red-winged Blackbirds Gone?

Female Red-winged Blackbird at Myakka River State Park, Florida
Female Red-winged Blackbird in winter at Myakka River State Park, Florida. Many references state that Red-winged Blackbirds are one of the most abundant birds in North America. But is this still really true? Canon EOS 7D/600mm f/4L IS (+1.4x TC). High-speed synchronized fill-flash.

A sighting of two female Red-winged Blackbirds eating cautiously from the seed feeders at the Edith L. Moore Sanctuary in west Houston on the afternoon of February 27 reminded me of what I saw recently in the north woods of Wisconsin and Minnesota. These suspicious birds were likely hungry migrants on their way north, to perhaps the very same Great Lakes region habitats I visited last summer.

After that trip, I wrote about ecological changes I observed  birding the woods of northern Wisconsin and Minnesota. One of those changes was an apparent drastic reduction in the number of Red-winged Blackbirds in a variety of habitats relative to what I remembered from childhood. Rather than large flocks in cattail marshes and around the margins of lakes and rivers, I saw only scattered small groups of fewer than ten birds.

In 2009 APHIS, part of USDA, says it poisoned 489,444 red-winged blackbirds in Texas, and 461,669 in Louisiana.—Martha Rosenberg,

Further reading after these observations substantiated impressions of massive population losses. Ever since that time, I have kept an eye out for these birds wherever possible. I am aware, however, that reports based on anecdotal evidence will likely convince no-one, especially those with a vested interest in denial.

Singing Male Red-winged Blackbird at Brazos Bend State Park, Texas.
Singing Male Red-winged Blackbird in winter at Pilant Lake, Brazos Bend State Park, Texas. Canon EOS 7D/600mm f/4L IS (+1.4x TC). High-speed synchronized fill-flash.

The “famous” taxpayer-supported USDA program of mass poisoning of icterids (blackbirds, grackles, cowbirds) and other agricultural pest species like magpies and European Starlings called “Bye bye blackbird”  is probably just the tip of the iceberg of officially sanctioned avian extermination. I say famous because this is a well-known program widely reported on in the blogosphere—but never (to my knowledge) in the really “big time” popular media outlets, the ABC Evening News or the PBS Newshour, for example. (Sidebar: Why is this? Why must we look only to elite publications like Audubon’s  “Common Birds in Decline” or National Geographic ‘s “Last Song for Migrating Birds” for reports of the destruction of the environment and the slaughter of its innocents? I guess it would take time away from reports of Justin Bieber’s latest brush with the law and interviews with random passersby about the weather.)

Furthermore, the U.S. Fish and Wildlife Service (part of the Department of the Interior) has issued a directive, a so-called depredation order, that anyone can kill any number of pest birds they suspect of causing economic damage or posing health risks (sometimes with avicides like Starlicide and administered by professional contractors in the form of poisoned brown rice baits). These private activities are perhaps more disturbing than the USDA programs because of the much larger potential scale of the killing–and the USDA kills birds by the millions! In the eyes of the federal government (and many farmers) icterids are apparently vermin of no worth whatsoever—despite detailed agricultural studies showing that as a result of insectivorous blackbirds, farmers can use 50% less pesticide.

For me, the bold, difficult to describe call of the Male Red-winged Black-bird is the sound of a marsh. Males perched atop cattails with females poking around in the brush below is what a marsh is supposed to look and sound like. Should the Red-winged Blackbird go the way of the Passenger Pigeon, marshes across North America will lose some of their most defining characteristics and aesthetic qualities—the experience of visiting a marsh will be immeasurably degraded.

Perhaps the plight of the Rusty Blackbird will focus some more attention on systematic, deliberate avian extermination. Rusty Blackbirds have suffered an estimated 85-98% reduction in population over the past 40 years likely due, in part, to agricultural poisoning by the government and private individuals. The Rusty Blackbird (along with the Mexican Crow) has been removed from the depredation order—at least taxpayers are not paying for the extermination and protection of the same species. Perhaps that’s all we can hope for in the current Age of Dysfunction—although I fail to understand how Rusty Blackbirds and Mexican Crows will be kept from eating the poisoned rice.

Male Great-tailed Grackle at East Beach, Galveston Island, Texas
A Male Great-tailed Grackle Intimidates Rivals Over a Seagull Carcass at East Beach, Galveston Island, Texas. According to the federal government such birds are vermin and can be killed with impunity. Canon EOS 7D/600mm f/4L IS (+1.4x TC). High-speed synchronized fill-flash.

I value my garden more for being full of blackbirds than of cherries, and very frankly give them fruit for their songs.—Joseph Addison, The Spectator

©2014 Christopher R. Cunningham. All rights reserved. No text or images may be duplicated or distributed without permission.

Look-a-like Little Sandpipers: Charmers of the Winter Mudflats

Western Sandpiper at East Beach, Galveston Island, Texas
Hunting Western Sandpiper (Calidris mauri) on a Beautifully Rippled Surface at East Beach, Galveston Island, Texas. Canon EOS 7D/600mm f/4L IS (+1.4x TC). High-speed synchronized fill-flash.

East Beach, Galveston Island, Texas at low tide is a magical place: a place equally suited for a biology or geology field trip. Gorgeous bedforms of a dozen kinds—those structures formed by the action of water on sediments like ripple marks and dunes—bring back memories of sedimentology classes many moons ago. Running around on theses surfaces (or occasionally trying to pry a recalcitrant worm from the sand and mud) are the sandpipers.

Dunlin at East Beach, Galveston Island, Texas
Dunlin (Calidris alpina) at East Beach, Galveston Island Texas. Canon EOS 7D/500mm f/4L IS (+1.4x TC). Natural light.

In their winter colors, the smallest ones, Sanderlings, Dunlins, Least Sandpipers, and Western Sandpipers sometimes test the birder’s ability to distinguish one species from another. In this endeavor, behavior is often just as good a guide to identification as are the details of appearance.

Sanderlings are perhaps the most charming and easiest to identify of the sandpiper clan as they chase the waves as they drain back out to sea, plucking stranded invertebrates and detritus as they go. Dunlins typically poke about at the strand line, and Western Sandpipers often explore the puddles of the intertidal zone. Least Sandpipers tend to probe for food along the margins of vegetation.

Sanderling at East Beach, Galveston Island, Texas
Sanderling (Calidris alba) in Frosty Winter Colors at East Beach, Galveston Island, Texas. Canon EOS 7D/500mm f/4L IS (+1.4x TC). Natural light.

Although I tend to notice sandpipers most often in intertidal habitats, all of these birds can also be found in freshwater and terrestrial environments such as the margins of lakes, flooded fields, and freshwater marshes. All birds mentioned in this post are still common, but Dunlin and Sanderlings are declining in numbers, mainly due to human use (and misuse) of beaches and other coastal habitats . . . yet another tragic tale of our time.

Least Sandpiper at Brazos Bend State Park, Texas.
Least Sandpiper (Calidris minutilla) in a freshwater marsh, Pilant Lake, Brazos Bend State Park, Texas. Canon EOS 7D/600mm f/4L IS (+1.4x TC). Thanks to TE for pointing out these little fellows. High-speed synchronized flash.

Someday, after mastering the winds, the waves, the tides and gravity, we shall harness for God the energies of love, and then, for a second time in the history of the world, man will have discovered fire.—Pierre Teilhard de Chardin

©2014 Christopher R. Cunningham. All rights reserved. No text or images may be duplicated or distributed without permission.

Of Limpkins and Applesnails

Limpkin at the Celery Fields, near Sarasota, Florida
Limpkin on a Snail Hunt at the Celery Fields, near Sarasota, Florida. We had hoped to get a shot of a Limpkin eating a snail, but the four birds we saw would find snails and then high-tail it back into to the vegetation to eat them, only to reappear a few minutes later to continue the hunt. Canon EOS 7D/600mm f/4L IS (+1.4x TC). Natural light.

On a recent birding to trip to Florida we were excited to see Limpkins, odd rail-like birds that feed primarily (75%) on applesnails. Limpkins are snail specialists with slightly right-curving beak-tips to reach inside snail shells. Historically, Limpkins have fed on the Florida Applesnail, the one indigenous U.S. applesnail species. However, the U.S., especially the Gulf Coast, is currently under invasion by several additional species of Neotropical applesnails (Genus Pomacea, but we’ll leave the contested details of which species are which to the gastropod taxonomists!).

Two species of snail-eating birds  appear to be taking advantage of this invasion: Limpkins and Snail Kites. Limpkins are reportedly expanding their range in Florida to harvest the explosion of invasive snails, and the Florida subspecies of Snail Kite appears to be rebounding from the brink of extinction based on the proliferation of prey. White Ibis also dine on applesnails and may be benefitting from increased food supplies.

Although these invasive mollusks seem to be benefiting these birds, many naturalists fear the applesnail invasion. These snails have become major agricultural pests in other parts of the world where introduced, and some species host the rat lungworm parasite (now doesn’t that sound pleasant?). Even in death applesnails pose a threat: shells discarded by Limpkins and Snail Kites serve as water reservoirs for the breeding of invasive Asian tiger mosquitos.

Seems that everywhere we go on our birding adventures we find invasives (or their impacts), or in researching these posts, read about the impacts invasives have on birds or the environment in general. Pristine environments are now non-existent. Even in parks and preserves billed as being “native,” cursory inspection of land or water soon usually reveals invasives, be they Chinese tallow trees, water hyacinth, Hydrilla, or privet—or applesnails. I somehow doubt, though, that Limpkins and Florida Snail Kites will accompany the applesnail invasion of Texas. Pity.

Apple Snail Egg Mass at El Franco Lee Park, Houston.
Applesnail (Pomacea sp.) egg mass at El Franco Lee Park, south Houston. Egg masses can be found on emergent vegetation in shallow water. Canon EOS 7D/500mm f/4L IS (+1.4x TC). Natural light.

Time sometimes flies like a bird, sometimes crawls like a snail; but a man is happiest when he does not even notice whether it passes swiftly or slowly.—Ivan Turgenev

©2014 Christopher R. Cunningham and Elisa D. Lewis. All rights reserved. No text or images may be duplicated or distributed without permission.

Birding Myakka River State Park: Brazos Bend State Park’s Florida Cousin

Tricolored Heron with Warmouth at Myakka River State Park, Florida
Too big? Tricolored Heron with Warmouth at Alligator Point, Myakka River State Park, Florida. Alligator Point is on an oxbow lake. After trying to swallow the fish a few times, this bird eventually gave up and walked away. Canon EOS 7D/600mm f/4L IS (+1.4x TC). Natural light on a dark, gloomy day.

Over the past week we were able to spend a few days at Myakka River State Park (MRSP) in western Florida near Sarasota. We were struck immediately by similarities to Brazos Bend State Park, Texas (BBSP). Both are subtropical low-relief state parks centered around rivers and lakes. The winter water bird avifaunas are also similar–with a few exceptions, Wood Storks and Double-crested Cormorants having the most conspicuously different abundances at the two parks.

Over the years I have only seen one Wood Stork at BBSP. On the other hand, Wood Storks proved to be common at MRSP during our stay, and we were able to observe them in flight overhead, underwing hunting/fishing and “wing flashing” (herding aquatic prey by waving a wing) at Alligator Point. The oxbow lake at Alligator Point provides the birder or photographer an excellent vantage point to observe bird behavior deep off the beaten track—but watch out for poison ivy! Pied-billed Grebes are present in small numbers (relative to BBSP) at MRSP, but Double-crested Cormorants are abundant and making a living the way the grebes do at BBSP, namely diving after prey in shallow freshwater lakes.

Double-crested Cormorant at Alligator Point, Myakka State Park, Florida
Double-crested Cormorant at Alligator Point, Myakka State Park, Florida. Canon EOS 7D/600mm f/4L IS (+1.4x TC). Natural light.

The prey are conspicuously different at these two parks, however. At this time of year at BBSP the birds seem to be consuming a mix of fish, amphibians (frogs and salamanders), and arthropods. At MRSP we only saw fish being taken–several species of gar, Tilapia, bass, and small catfish . . . although one Great Blue Heron was convinced he had a snake or Amphiuma salamander and pecked a poor stick to bits! The absence of crawfish prey struck me as remarkable, and I asked a ranger about it. He said that during the dry season, the crawfish remain in their burrows. Perhaps when the rains return and some the low-lying areas flood again, crawfish will be on the water bird menu.

In general, our time in western Florida has brought up a number of fascinating topics for thought, research, and future travel plans that will no doubt be discussed in this blog at some point in time. How are Tilapia (an invasive), for example, impacting the environment generally and wader diets in particular. Also, where are the amphibians? Could we be seeing another example of the global amphibian crisis? These questions make me want to bird this amazing park during other times of the year.

Wood Stork canopy fishing at Myakka State Park, Florida
Double Wing Fishing(?) Wood Stork at Alligator Point, Myakka River State Park, Florida. By creating a shadow, the under-wing-fisher can better see through the glare and spot prey beneath the surface. Reddish Egrets are best known for this technique, but this Wood Stork appeared to be using the same approach. The Wood Stork is considered an Endangered Species by the U.S. Fish and Wildlife Service. Canon EOS 7D/600mm f/4L IS (+1.4x TC). Natural light.

My parents didn’t want to move to Florida, but they turned sixty and that’s the law.–Jerry Seinfeld

©2014 Christopher R. Cunningham. All rights reserved. No text or images may be duplicated or distributed without permission.

Hummingbird Travelog Part 1: The Oasis Effect

Juvenile male Rufous Hummingbird in flight
Juvenile male Rufous Hummingbird making a play for an open feeder spot at the Franklin Mountains State Park bird blind. Canon EOS 7D/500mm f/4L IS (+1.4x TC). Natural light. 7.26.2013.

All systems in nature seek the lowest available energy state. This is a concept that my students could always grasp on a personal level. (Substitute “teenagers” for “all systems in nature” in the first sentence. See what I mean?) Human nature, like the rest of nature, tends to follow the path of least resistance. Hummingbirds are no different.

Consider the droves of hummingbirds attracted to sugar-water feeders. Well-kept feeders are an easy alternative to foraging, and field studies show that when nectar (or nectar substitute) sources are super abundant, high metabolic cost territorial activity decreases. Feeders are the path of least resistance for hummingbirds.

Human interest in hummingbirds and the resulting dedication to supplementing their diet has impacted their biogeography. Hummingbird banding data support the idea that feeders (along with native gardening practices) are the reason that overwintering hummingbird populations have expanded along the Gulf Coast after first migrating into Mexico in the fall. Feeders and native plantings also contribute to the so-called “oasis effect” observed in exurban developments in the arid southwest where increasing numbers of hummingbirds (among other birds) in resource-poor terrain take advantage of supplemental food, shelter, and water resources.

Hovering male Calliope Hummingbird drinking from a sugar-water feeder
Male Calliope Hummingbird taking advantage of the sugar-water feeders at the Franklin Mountains State Park bird blind in July. Canon EOS 7D/500mm f/4L IS (+1.4x TC). High-speed synchonized flash. 7.26.2013.

On our recent summer desert birding road trip, we found the Franklin Mountain State Park feeders buzzing madly with hummingbirds. Especially welcome was the opportunity to get close-up views of Calliope Hummingbirds – thought to be the smallest long-distance avian migrant in the world – on their 5,000 mile southern journey to Mexico from the northwestern US and Canada.

For Calliopes, fall migration starts early. Sources report typical Calliope departures from northwest locales in late August. But wait, it was late July and they were already in Texas … Was this early arrival due to a natural seasonal shift or could it just have been the oasis effect?

I hear like you see — like that hummingbird outside that window for instance.

— Ray Charles


 © 2013 Elisa D. Lewis. All rights reserved. No text or images may be duplicated or distributed without permission.

Birding Northern Wisconsin: Notes on a Changing World from the North Woods

Dunlin in breeding colors at Ashland, Wisconsin
Dunlin in Breeding Colors on the south shore of Lake Superior, near Ashland, Wisconsin during mid-June. We typically see Dunlin in their winter plumage along the Texas Gulf Coast. Canon EOS 7D/500mm f/4L IS (+1.4x TC). Natural light.

We usually take two to three major birding trips outside the Texas Gulf Coast region each year. We strive to visit many different types of habitats, with the hopes of seeing as many different species of plants and animals as possible.

This week we returned from a trip to northern Wisconsin and Minnesota. We spent most of our time in the Chequamegon-Nicolet National Forest and along the southern shore of Lake Superior, primarily at the Apostle Islands National Lakeshore. Besides seeking a brief respite from the Texas heat, we were eager to explore the cool temperate broadleaf and mixed forests. We found these forests to be among the most beautiful and botanically diverse woodlands we have ever encountered, rivaling the temperate rain forests of the Pacific Northwest aesthetically. Many species of songbirds and others that migrate through Texas in the fall and spring nest in these forests. We had hopes of hearing their summer songs and seeing their summer colors.

Having grown up in Minnesota and visited similar habitats in Northern Minnesota and Wisconsin many years ago, I thought I knew what to expect. I remember taking field trips for undergraduate geology courses in Minnesota and Wisconsin in the 1980’s and noticing the great abundance of wildlife. Sadly, a great abundance of wildlife was not what we found on this trip.

Mixed Broadleaf forest of the Chequamegon-Nicolet National Forest, northern Wisconsin
Spectacular, but Strangely Sterile: Mixed deciduous broadleaf and coniferous forest of the Chequamegon-Nicolet National Forest, northern Wisconsin in mid-June. Here and there we heard a singing male Northern Parula or Chipping Sparrow. Otherwise, it was pretty quiet. Canon EOS 7D/Tokina 11-16mm f/2.8 @ 16mm. Hand-held, natural light.

Amphibians are now rare in northern Wisconsin. For someone with childhood memories of woods hopping with toads and alive with frog song, what I found was shocking. Marsh, bog, swamp, and adjacent woodland habitats that should have been noisy with Northern Leopard Frogs (Rana pipiens) were nearly silent. A quick check of on-line references found numerous references to catastrophic declines in Northern Leopard Frog numbers in the past few decades.  The rarity of amphibians helps to explain the rarity of waders hunting in the vegetated shallows of lakes and marshes: we saw only a handful of Great Blue Herons and a single Green Heron. The silence of these northern Wisconsin woods is grim testimony to the global amphibian crisis.

Strangely, even Red-winged Blackbirds are not that abundant anymore. In one marsh I noted three birds: and one was banded! What gives? According to the AMNH Birds of North America, Red-winged Blackbirds are one of the most abundant birds in North America, known for moving around in vast flocks. Again, a quick internet search revealed references to major declines in Red-winged Blackbird populations in the northern Midwest and Canada (apparently I’m not going crazy!).

Birds that are abundant include American Crows, European Starlings, and Brown-headed Cowbirds–not surprising since these species thrive around humans and the environmental changes we cause. Brown-headed Cowbirds, of course, are contributing to the decline of songbird numbers (terrifyingly so) through nest parasitism of about 220 species. According to the video Gulf Crossing: An Essay on Bird Migration, we have lost about 40% of our songbirds in the past 25-30 years due to several causes. Based on what I have seen in the north woods, I would not be surprised if losses were significantly higher.

Birds may be suffering, but nasty arthropods are proliferating. North woods habitats are typically quite buggy in late spring and early summer, but what we found was really quite mind-boggling, and rivaling the most bug-infested salt marsh environments we’ve ever encountered (our Original Bug Shirts kept us alive!). Local after local (including some old-timers) described the bug situation as the worst they had ever seen with respect to mosquitos, wood ticks, and deer ticks (And don’t forget gnats!). One local remarked how at one point he simultaneously had three Lyme disease bull’s-eyes on his body. A quick internet search revealed articles (not surprisingly) blaming climate change for the bug infestation (Hmmmm.)

White-tailed Deer, too, are everywhere in huge numbers. I saw more White-tailed Deer than squirrels! Estimates are that White-tailed Deer populations in Wisconsin have increased 600% since 1950. This is probably due to humans feeding them and killing off predators such as wolves and mountain lions. Silly humans. White-tailed Deer abundance correlates negatively with songbird abundance because of the way deer graze away the understory vegetation.  I was shocked to learn recently that White-tailed Deer are known to eat bird nests, including eggs and nestlings, of ground- and understory-nesting birds. Habitats can only sustain a limited number of large ungulates. Cross a numerical threshold and ecosystems collapse. Northern Wisconsin has apparently crossed that threshold.

Bull Elk at Yellowstone National Park, Wyoming.
Bull Elk at Yellowstone National Park, Wyoming. Overpopulation of Elk at Yellowstone led to overgrazing of willow and aspen saplings and decimation of songbird populations. When Elk-munching wolves were re-introduced into the park in 1995 songbird populations expanded. Canon EOS 7D/100mm f/2.8L IS macro. Hand-held, natural light.
White-tailed Buck at Laguna Atascosa National Wildlife Refuge, Texas
Eight Points, Four Western: White-tailed buck at Laguna Atascosa National Wildlife Refuge, Texas. White-tailed Deer are wreaking the sort of havoc on ecosystems across eastern North America that excess Elk brought to Yellowstone. These fuzzy villains have got to be brought back into balance! Canon EOS 7D/100-400mm f/4.5-5.6L IS. Hand-held, natural light.

Until recently I have been in the doubting camp as far as anthropogenic climate change has been concerned. My general sense of the climate has been that it is consistent with heading deeper into an interglacial regime, with warmer average temperatures and decreased equability. These periods are associated with loss of biodiversity and stormy frontal weather patterns in the higher latitudes. I thought current climatic changes could probably be explained by Milankovitch cycles, perhaps in conjunction with variation over time in solar subatomic particle production and the amount of cloud cover produced as reported by CERN. An excellent recent summary article has led me to re-evaluate my position. On the other hand, I am not at all skeptical that humans are destroying the environment globally in other ways. That we are in the midst of an anthropogenic mass extinction event is beyond question. One need look no further than Wisconsin, Texas, or wherever you live.

©2013 Christopher R. Cunningham. All rights reserved. No text or images may be duplicated or distributed without permission.

Birding the Future

Pencil drawing of a Ruby-throated Hummingbird by a young artist.
Trepp’s interpretation of my Ruby-throated Hummingbird image. Nature illustration is one of many ways young people express their interest in and curiosity about the natural world.

We don’t often see children out birding. Frankly, as high school teachers, we inked that feature into the “pros of birding” column when we were auditioning feasible hobbies. Children, it seems, neither make happy birders nor birders happy.

A Ruby-throated Hummingbird feeds from a lantana flower cluster at Lafitte's Cove Nature Preserve on Galveston Island, TX.
A Ruby-throated Hummingbird feeds from a lantana flower cluster at Lafitte’s Cove Nature Preserve on Galveston Island, TX. Notice the dusting of pollen on his head
Portrait of Chris Cunningham in pencil by a young artist
Trepp captured Chris discussing our camera set-up during the HANPA April 2013 meeting.

It may seem ironic but, we were pleasantly surprised to see two young visitors to our “Behind the Blog” presentation at the Houston Audubon Nature Photography Association (HANPA) meeting in April. (Willing students are always appreciated!) Brothers Richard and Trepp, eight and six, stayed as long as their bedtime would allow. We were impressed by the quality and depth of their questions and received several wonderful sketches capturing parts of the program. Encouraged by this passionate interest at such a young age, I was reminded that birders need to cultivate the next generation of birders if bird conservation – let alone nature conservation – is to have a future.

Flashback to the late 1990’s when Chris and I lived in Austin: We were the only “kids” in the creek beds during school-term weekends.  We were re-living our childhood–where were the real kids spending theirs? Was this a generational shift to the indoors or a shift born of crime statistics, real and imagined?  My parent friends tell me it was fundamentally the latter. Computer activities were (and presumably still are) the safer option. How do we foster exploration and conservation if the great outdoors needs a chaperone?

It’s up to us. How will you bird the future?


“The future depends on what you do today.”

— Mahatma Ghandi

Pelican Pouches and the Power of Citizen Science

Eastern Brown Pelican with red throat pouch at Offatts Bayou, Galveston Island, Texas.
A Brown Pelican with a red throat pouch glides past the shore at Offatts Bayou, Galveston Island, Texas on February 3, 2013. Many references suggest that Brown Pelicans with red throat pouches only occur along the Pacific Coast. Field observations suggest otherwise!

While we were watching the loons at Offats Bayou in early February, a Brown Pelican paddled through my viewfinder. Odd, I thought — red pouch. After much hopeful discussion and reference checking we were excited to think that we had a California Brown Pelican visiting our patch of the Texas Gulf Coast. There are five subspecies of Brown Pelican — the California, Caribbean, Eastern (ours), Galapagos, and Ecuador Brown Pelicans. The gular pouch of the Eastern Brown Pelican (Pelicanus occidentals carolinensis) is most often described as dark gray or blackish, whereas in the California Brown Pelican (Pelicanus occidentals californicus) the pouch is a distinctive red and olive. The difference has been used to distinguish the two subspecies.

Eastern Brown Pelican with black gular pouch
Adult Eastern Brown Pelican with the typical black gular pouch seen in early spring along the Gulf Coast.

As is often the case, things aren’t always as they seem (I love it when this happens!). Upon further investigation, I stumbled upon a post in Sibley Guides online which explains that red pouches seem to also be a part of the Eastern Brown Pelican gene pool based on field observations. The post includes speculation on whether these genes were introduced during Brown Pelican reintroduction in the 70’s or whether it’s really a matter of natural gene flow. Perhaps it’s a little from column A and a little from column B. The observation poses a bunch of new questions to investigate!

Strangely enough this topic was just mentioned on ABA Birding News this past Thursday. A birder/photographer documented a banded Brown Pelican with a red pouch and the band code indicated it was banded as a flightless juvenile in Louisiana — photographic proof that we can no longer use pouch color alone to differentiate Pacific vs. Atlantic subspecies! It seems our “visitor” is most likely a Texan after all.

It is worth noting that this “pelican brief” was brought to you by citizen science and the power of the internet to access and share data. Enthusiasts and amateur scientists interested in birds and their ecology contribute to ornithology in meaningful ways. Opportunities are out there for birders of all ages. You can participate nationally with  Cornell All About Birds Citizen Science projectsAudubon Citizen Science, or eBird – the amazing biodiversity data resource powered by amateur and professional bird watchers alike launched by the Cornell Lab of Ornithology and National Audubon Society in 2002.

Go exploring!

 © 2013 Elisa D. Lewis. All rights reserved. No text or images may be duplicated or distributed without permission.

Where the Loons Are

Common Loon in winter plumage head shot
Common Loon in winter plumage fishing Offatt’s Bayou close to shore.

One of our favorite birding tools is the excellent guidebook Finding Birds on the Great Texas Coastal Birding Trail: Houston, Galveston, and the Upper Texas Coast by Ted Eubanks. Last weekend, tempted by Eubanks’ description of loons often feeding a few feet from shore, we visited Galveston’s Offatt’s Bayou (site 65 on the Great Texas Coastal Birding Trail). Not only did we have multiple opportunities to watch Common Loons up close but the loons seemed unperturbed by humans — we witnessed loons popping up as close as 3 feet away as we sat on the fishing dock. Indeed, a local fisherman complained to us that the loons often steal his bait while underwater.

According to Eubanks, a visit in late April just before migration should provide views of Common Loons in their distinctive checkerboard breeding plumage. Although their winter plumage is drab by breeding plumage standards, it was fascinating to watch them hunt. Swimming by, they peered underwater, moving their heads side to side presumably searching for prey. After one dive, a loon came up with a small crab and then swallowed it whole. This hunting strategy requires clear water which is why you can find loons in Offatt’s Bayou and other deep, non-silty bodies of water. Our previous experience at Texas City Dike produced many loons but Offat’s Bayou wins hands down for reliable up close photographic opportunities.

All five species of North American Loons are known to winter around the Gulf of Mexico. However, only Common Loons are common around Galveston Bay.  And although tolerance of humans allows for more intimate views (or a pre-caught lunch), sharing fishing holes has not been entirely positive, for loons or loon watchers. A quick survey of the web indicates that lead poisoning from fishing tackle is a leading cause of mortality in loons – not to mention other other wildlife. I was encouraged to read however, that anglers and conservationsists in a few Common Loon breeding ground states have successfully implemented economically viable non-lead fishing tackle alternatives.

Most likely juvenile Common Loon in winter plumage fishing in Offatt's Bayou, Galveston Island, Texas
Juvenile Common Loon or rare Pacific Loon? Although this loon looks like an adult non-breeding Pacific Loon, it is missing a dark partial throat band. Most likely it is a juvenile Common Loon. Loon watchers: please let us know your thoughts.

© Copyright 2013 Elisa D. Lewis. All rights reserved. No text or images may be duplicated or distributed without permission.

Why Birders Should Care About the Global Amphibian Crisis

Little Blue Heron with tadpole at Brazos Bend State Park, Texas
Little Blue Heron with Tadpole at Brazos Bend State Park, Texas Gulf Coast.

Over the past several decades the diversity and abundance of Amphibia have declined precipitously: estimates for the amphibian extinction rate range from tens to tens of thousands of times the typical background rate of species loss. Despite conservation efforts (Amphibian Ark) and some publicity, most people I speak to are completely unaware of this catastrophic decline. Over the past decade or so, it has become clear that there are several major causes. The most important appears to be habitat loss. As freshwater swamps and marshes are drained to build the endless suburban sprawl of tract housing, and forests are bulldozed into the chippers, amphibian habitats are dwindling. Acidification of lakes and ponds, other forms of pollution, and an infectious fungal disease (chytridiomycosis), are also implicated.

American Bullfrog at Brazos Bend State Park, Texas
American Bullfrog (Rana catesbiana) at Brazos Bend State Park, Texas. American Bullfrogs are an abundant food source for waders along the Texas Gulf Coast. Luckily, bullfrogs appear to have resistance to chytridiomycosis.

Many think that the reason amphibians have been among the hardest hit groups in the current anthropogenic mass extinction event (the Holocene mass extinction) is because these animals have aquatic larval stages and a terrestrial or amphibious adult stage, and can be negatively impacted by changes in both the aquatic and terrestrial environments. The process of metamorphosis, which typically occurs in an aquatic environment (or at least an aqueous one–think about the bromeliad treefrog!), is biochemically sensitive. For these reasons, some refer to amphibians as the “canaries in the coal mine” of ecosystems.

Olympic Peninsula, Washington
Northern Red-legged Frog (Rana aurora) at Olympic National Park, Washington. In some places, the ground-cover vegetation of the temperate rain forests of the Pacific Northwest is alive with amphibians.

As a photographer, one of my favorite subjects is hunting waders: please see Stalking the Hunters. Along with fish, crawfish, and aquatic insects, amphibians (primarily frogs and tadpoles, and to a lesser extent salamanders) form a staple of the wader diet. Other predatory birds, Loggerhead Shrikes, for example, also eat amphibians. Shrikes are fascinating birds known to kill their prey by impaling it on sharp objects, usually thorns. On one, and only one, occasion we heard what we thought was a frog call coming from above. We looked up to notice a Loggerhead Shrike on wire over a frog-filled bayou. Was this a simple case of mimicry? Or deception—trying to get a frog to divulge its location? Research turned up no mention of Loggerheads making frog calls. Shrikes are known to deceive each other away from kills with frightening false alarm calls–so they’re not above trickery. The Asian Rufous-backed Shrike is an accomplished mimic, and, of course, the Northern Mockingbird is known to mimic frog calls, but a Loggerhead Shrike? We will continue to keep our eyes and ears peeled for this phenomenon.  If we heard what what we think we heard, we hope the time a Shike’s frog-call goes unanswered never comes.

Shrike-impaled Green Tree Frog on rose thorn, Sabine Woods, Texas
Green Tree Frog (Hyla cinerea) on Rose Thorn. Elisa captured this macabre image of a Loggerhead Shrike-impaled tree frog at Sabine Woods, Texas Gulf Coast. The shrike had just killed this frog and a mouse, whose decapitated body was impaled on some more rose thorns and whose head was impaled on some nearby barbed wire. As soon as Elisa finished the shoot and walked away, the shrike returned and reclaimed the mouse’s head.

 © 2012 Christopher R. Cunningham and Elisa D. Lewis. All rights reserved. No text or images may be duplicated or distributed without permission.

Fall and Winter Fruits . . . Ah, the Irony. . . .

Knowledge is knowing that a tomato is a fruit. Wisdom is knowing not to put it in a fruit salad. –Brian O’Driscoll

One of the treats of birding in the cooler months is watching for birds enjoying the many types of conspicuous fruits and berries that can be found in the woodland habitats of the Texas Gulf Coast. Yaupon holly (Ilex vomitoria), greenbriar, and agarita are just a few of the many examples of native plants bearing brightly-colored berries during fall and winter that are popular with birds. As a photographer I always have an eye out for a Cedar Waxwing, American Robin, Northern Mockingbird, or Northern Cardinal with a rosy-ripe and juicy berry in its beak.

As a novice field botanist, I often photograph newly encountered fruit-bearing plants with the hopes of later identifying them. It soon becomes evident, however, that the landscape is dotted with exotic fruit-bearing plants from around the globe–escapees from gardens, seeds sown through the digestive tracts of birds or mammals. Sometimes they are identifiable, sometimes not.  I’m sure some of the species that I find impossible to identify are, to landscapers and nurserymen, commonly-known, popular garden varieties–from South America, the Caribbean, or that great cradle of Angiosperm evolution, Northern China.

A House Finch Eats Chinese Tallow Fruit. Federal biologists imported Chinese tallow into the U.S. in 1905. This plant is now taking over many forests of the South. Photo taken in Houston, Texas. Canon EOS 7D/500mm f/4L IS (+1.4x TC).

It might be tempting to suppose that these introduced species may be harmless or even helpful to birds, given that they produce edible fruits. Species of Pyracantha, for example, are commonly encountered invasives that produce copious amounts of bird-friendly fruit–and birds are implicated in the spread of these Eurasian plants. The Chinese tallow tree is another common invasive. Chinese tallow may be the greatest challenge, after man himself, to the warm native forests of North America. About 23% of all trees in the Houston area are now Chinese tallows.

In contrast to many of the natives, some of these foreign plants seem strangely sterile: not an arthropod of any kind is to be seen on them. As these foreign invaders have proliferated, robbing pollinators and insectivorous birds, displacing and replacing native ecological equivalents, songbird numbers have declined an estimated 40% in my lifetime. Of course, it’s hard to prove which aspect of humankind’s activities–chopping, plowing, spraying, shooting, paving, or planting foreign invasives has been most disastrous for our birds–but to me it doesn’t really matter–it’s all of a piece. Homo sapiens sapiens, the Yersinia pestis, of the planet’s biosphere marches unrelentingly on  . . . We are, it seems, in the midst of an anthropogenic mass extinction event. And the Dodo, Ivory-billed Woodpecker, Passenger Pigeon, Carolina Parakeet and Hawai’i Mamo bore witness. . . .

Pyracantha sp,, in Houston, Texas
Pyracantha, a Eurasian invasive, is displacing native plants. The brightly-colored berries are attractive to birds that disperse the seeds. Photo taken in Houston, Texas. High-speed synchronized flash.

©2012 Christopher R. Cunningham. All rights reserved. No text or images may be duplicated or distributed without permission.