Common Gallinules at the Refuge

Over the last few years, Common Gallinules have become more common at Sam D. Hamilton Noxubee National Wildlife Refuge during the winter.  While they have long been regular summer residents in the area, the overwintering is apparently a fairly recent development.  Is it a bad sign?  A good one?  Neutral?  I'm not entirely sure.  I suspect that it may be related to climate change (in this case, increasingly warm winters in north Mississippi), so it's certainly a potentially concerning development, and worth monitoring.

During the winter, these Noxubee NWR gallinules spend most of their time around the edges of the lakes, and occasionally mingle with American Coots.  Here are some photos:

The Gallinule is to the right of the American Coot

Gallinule -- note the white lines on the sides of the body.

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Lots of foraging in the shallows!

The lake.  What you can't see is the biting wind!

Seasonal Changes at Noxubee National Wildlife Refuge

Although it seemed at first that it might take a while for the Southeast to recover from the ice storms of last February, spring weather has pushed its way into most of these previously frozen areas.  As many readers are already well aware, I frequently visit Sam D. Hamilton Noxubee National Wildlife Refuge to enjoy the natural sights.  I did just that a few days ago.  The woods at Noxubee are beautiful right now, with plenty of blooming trees, such as flowering dogwood.  The cypresses that grow all around the two main lakes have just started unfurling their leaves, and the oaks and redbuds have nearly completed their leafing-out.

Flowering dogwood

The birdlife at Noxubee is in the process of a changeover, with winter residents—such as ducks and most of the sparrow species—leaving the area, and the summer residents—including Purple Martins, Northern Parulas, some types of wading birds, and warblers—settling in.  That is exactly what’s happening right now at Bluff Lake.  In this photo from earlier in the month, you can see an enormous raft of American Coots: 

However, near the end of the month, the coots are nearly all gone from the refuge:

Instead, what can be seen from Bluff Lake right now are the Great Egrets beginning their breeding period.  They roost and nest in the cypress trees over the water.  Cattle Egrets, Little Blue Herons, White Ibises, and several other species also use these trees, but the population of Great Egrets at this location has really exploded in recent years, likely as a result of the trees growing taller.  The smaller Cattle Egrets still nest at the lake, but their numbers are a bit lower than they were a decade or two ago.

Great Egrets at heronry

Little Blue Herons are very common at the refuge, as well, even though they never appear in numbers as high as those of Cattle and Great Egrets.  These Little Blues can be seen foraging in one of the marshy shorelines of Bluff Lake.  Their slate blue coloration is distinctive, and they are unlikely to be confused with other herons in this part of the country.  Unlike the adults, though, juvenile Little Blue Herons are almost entirely white, with touches of gray on their wingtips.  They acquire a patchwork white-and-blue appearance as they gradually molt into adult plumage.

Little Blue Herons foraging in the grass

 

Little Blue Herons

Other spring water birds of note are Blue-winged Teal.  Although these small ducks generally do not overwinter in northern Mississippi in large numbers, flocks of them do pass through regularly during spring and fall migration.  The photo below shows two teal swimming in the shallows of Loakfoma Lake.  The male duck has a prominent white crescent-shaped marking on the face, while the female has buff-colored scallop markings on the wings and flanks. 

Blue-winged Teal

If you spend some time scanning the cypress and pine snags over the water or near the shore, you may spot a Bald Eagle or two.  These huge raptors nest at the refuge every year, and can often be detected by their startlingly chirpy, piping calls.  In the middle part of the 20^th century, Bald Eagle populations experienced sharp declines as a result of DDT poisoning, but they have since rebounded, and it now seems that nearly every large body of water in the Southeast may have a pair of eagles nearby.  But Bald Eagles’ commonness doesn’t take anything away from their amazing charisma, in my opinion.  No matter where I am, I love seeing them.

Yes, spring is here.  The temperatures are still fluctuating quite a bit, which is normal, but the heavy rains and strong storms, blossoming and leafing-out plants, and breeding and migrating birds signify the change in seasons. Be sure not to miss it!

Considering the Christmas Bird Count

American Coots (Lake Fayetteville, Arkansas, November 27, 2014)

The 101st Christmas Bird Count, back in December 2000, was my introduction to both my local Audubon Society chapter and the wider world of birdwatching.  Prior to that experience, I had birded mostly around my own yard in rural Mississippi, and certainly didn’t know anyone else who shared my avid interest in birds.  But all of that changed.  The count leader assigned my mother (who did the driving) and me to an area that included a portion of the local reservoir and dam, as well as the neighborhoods adjacent to it.  I remember standing at our first stop on the route, shivering in my heavy coat and thick gloves as I observed Bufflehead ducks and American Coots bobbing in the waves near the spillway.  Fortunately, the temperature increased considerably as the day progressed, as did the numbers on my bird checklist and my appreciation for this challenging but enjoyable form of citizen science.  What had originally been only a hobby for me was now a way to make a real contribution to ornithology.

The Christmas Bird Count is one of the longest-running wildlife censuses.  The period of December 14, 2017 through January 5, 2018 marks the 118th time that the count has been conducted.  Like many birdwatchers, I’ve already participated in my local CBC this year.  Some hardworking people will even be involved with more than one count.  The count circles, of which there are several per state or province, measure 15 miles in diameter, and each count compiler assigns portions of the count area to the various groups or individuals to cover.  The rules for counting are fairly simple: all observed, identified wild birds should be included in the tally, and the same area cannot be surveyed more than once.

American Kestrel seen on Noxubee NWR CBC, December 17, 2016

In addition to being a fun time in the field, the Christmas Bird Count is a great way to touch base with other birders and hone one’s birding skills.  While I normally do make an effort to keep accurate tallies of birds that I observe, the CBC forces me to pay even closer attention to what I’m seeing and hearing—to locate and identify every individual bird that I possibly can.  A lot of CBC work involves intensely focusing on details: listening carefully to detect all of the brief contact and alarm calls from sparrows, kinglets, warblers, chickadees, titmice, wrens, nuthatches, and creepers in the dense woods; scanning distant rafts of waterfowl for subtle differences in plumage between species; trying to get a reasonable estimate of the number of individuals in an enormous flock of blackbirds, robins, or waxwings; and so forth.

One of the most common songbirds seen in the winter months in North America: the White-throated Sparrow.  (Fayetteville, Arkansas)

The Christmas Bird Count began in 1900 as a response to the then-common “side hunts” that involved teams of hunters competing to see who could shoot the most animals—birds included—on Christmas Day.  The count’s founder, Frank M. Chapman, was a prominent ornithologist and conservationist who (quite understandably) found the tradition of “side hunts” to be irresponsible and repulsive, so he recruited a number of colleagues from all around the country to count all of the birds that they could find on Christmas.  Although the CBC has expanded considerably since its conception, its basic formula hasn’t changed much.  The fairly simple, straightforward rules make it just as fun for beginners as it is for those who have done it for years.

Considering how simple the CBC really is, how valuable could its results be to ornithology?  In some cases, more valuable than one might think.  For example, Niven et al. (2004) used CBC data to examine population changes in the bird species that breed in the boreal forests of Canada and Alaska and winter farther south.  Some of these boreal species, such as Merlins and Palm Warblers, showed population increases.  Populations of several other species were relatively stable, while some species, including Harris’s Sparrows, Rusty Blackbirds, and Northern Shrikes, had declined significantly.  The researchers noticed that the CBC winter population trends paralleled those in the data from the Breeding Bird Survey, another long-running bird census.

Merlin at Choctaw Lake, MS, December 31, 2015.

Like the authors of the boreal species study, Link et al. (2006) found that CBC data matched data from other surveys very well.  In this instance, American Black Ducks showed similar population changes on both the CBC and the Midwinter Waterfowl Inventory—an indication of the general accuracy of CBC data!  The data can also be useful for examining the impact of disease on bird populations; in 2003, C. Caffrey and C. C. Peterson looked at CBC results over a multi-year period for several common species in the northeastern U. S., and came to the conclusion that West Nile Virus had likely not significantly affected the populations in that region.  And these studies are merely the tip of the iceberg; CBC data can be a treasure trove of information for a patient researcher.  This is something worth celebrating about the CBC as the 118th count continues over the next week and as we move into a new year.

A rare (for the region) Palm Warbler seen on Noxubee NWR CBC, December 16, 2017.

References:

Caffrey, C. and Peterson, C. C.  2003.  Christmas Bird Count data suggest West Nile Virus may not be a conservation issue in the northeastern United States.  American Birds 57:14-21.

Link, W. A., Sauer, J. R., and Niven, D. K.  2006.  A hierarchical model for regional analysis of population change using Christmas Bird Count data, with application to the American Black Duck.  The Condor 108:13-24.

National Audubon Society, Christmas Bird Count Compiler Resources.  Retrieved December 30, 2017, from http://www.audubon.org/christmas-bird-count-compiler-resources.

Niven, D. K., Sauer, J. R., Butcher, G. S., and Link, W. A.  2004.  Christmas Bird Count provides     insights into population change in land birds that breed in the boreal forest.  American Birds 58:10-20.

Weidensaul, S.  2007.  Of a Feather.  Harcourt, Inc., Orlando, Florida, USA.