Tuesday, November 30, 2010

cypress-tree-meets-what-birds-eat

The prey: bald cypress seed cones/innards


     I was sitting on our back porch (nestled in the bottomland hardwood forests of northeastern Lafayette parish, Louisiana) around dusk on the evening of November 27 when my attention was drawn to the big bald cypress (Taxodium distichum) in our backyard about 25' away. Nearly leafless now, the tree is loaded with seed cones, fragments of which were clattering through its branches as they fell to the ground. Looking up, I was amazed to see a half-dozen or so male cardinals picking through the seed cones, dismantling them piece by piece. Were they actually eating cypress seeds?

The predator: northern cardinal
photo by Beth Erwin

 
     Apparently so. For the next half-hour, cardinals came and cardinals went, but the number feeding in the tree held steady at a half-dozen or so. Walking beneath the tree, all I found were empty cone husks on the ground. Whoa. This is the first time that I've noted a bird species of any kind feeding on cypress seed. I mean, I've heard that some birds do it, I've just never seen it for myself.

     Intrigued, I collected a couple of cones the next morning and dissected one. Surprisingly, the cones fell apart quite easily into myriad “chunks” resembling a sort of intricate, 3-D oriental puzzle, even though the exterior of each cone was still green. In between each component part was filled with a thin-but-sticky, yellow-green, and very aromatic/fragrant resin, smelling very much like “essence of Christmas tree.”

     Seedwise, however, I found nothing resembling a seed; but only tiny, lime-green, worm-shaped bodies. I tasted one. It crunched like a vegetable and proved nearly as aromatic in taste as the resin did in smell. Hmmm.

     So I consulted my all-time favorite native woody plant reference, Trees, Shrubs, and Woody Vines of the Southwest (Robert A. Vines, 1960; tree-lovers, ya'll really should grab a copy of this book from an online used book seller; information packed, covers 99% of Louisiana native woody plants, ultra-fine pen & ink drawings of each plant) and read me some.

     Under the “fruit” section of the bald cypress citation, Vines wrote, “Ripening in October-December, cone globose [roundish], closed, rugose [roughened]....formed by the enlargement of the spirally-arranged pistillate [female] flower scales [cypress flowers have scales instead of petals]....scales angular, horny, thick [see dark, chocolate-brown cone scales in photo above]; seeds 2-winged, erect, borne under each scale...”

     Hmm again. I did not see anything 2-winged and erect under each scale. All I saw were those green, crunchy, worm-like bodies. Moreover, each worm-like body came out of its own perfectly-shaped indention on the underside of the scale – like it really belonged there, you know? Was I looking at yet-underdeveloped seed? Perhaps so. Regardless, the cardinals were definitely eating it.

     The day before (Nov 26) I had seen a number of cardinals fooling with the cypress cones, but I guess I figured they were just “playing” with the cones. Silly human . . .

     Come to think of it, I now remember our big 2.5-year Atchafalaya Basin Bird Survey in 2002-04, where on a number of occasions I coaxed Greg Guirard to take me deep as he could into the swamp by boat so I could census the bird life there amongst permanently-flooded, pure stands of bald cypress/tupelo gum (Nyssa aquatica). As is the case with almost all climax forest systems, the diversity of bird life was relatively low in winter, consisting primarily of wood duck, osprey, several woodpecker species, yellow-rumped warbler (they're everywhere around here each winter), and, yes, cardinals. Understand, the closer to dry land you get in swamp systems, the more bird species you'll record; but once you get a half-mile or more from nearest land, the number of woodland songbirds drops percipitously. No more chickadees, titmice, gnatcatchers, kinglets, etc. Basically you're down to a few swamp specialists . . . so the, uh, robust presence of cardinals in the deep-swamp was striking.

     Were those cardinals feasting on bald cypress seed? I bet they were.

     Under his bald cypress citation, Vines adds interesting tidbits such as, “. . . the cone resin used as an analgesic [pain-killer] for wounds,” and, “The seeds are eaten by a number of species of birds, including wild ducks.” and “. . . has been known in cultivation in Europe [far from its native southeastern U.S. range, non?!?] since about 1640,” and “Fossil ancestors of bald cypress, at one time, covered the greater part of North America in company with the ginkoes, sequoias, and incense-cedars.”

fall has fallen

Nutmeg Hickory Leaf (Carya myristiciformes)
26 Nov 2010, Lafayette Parish




“But ask the beasts, and they will teach you;
the birds of the air, and they will tell you;
or the plants of the earth, and they will teach you...”

Job 12:7



      Down here on the Gulf Rim – at the continental border of temperate and tropical air masses – the seasons of the year tend to run into one another, making it difficult to know where one ends and another begins. Throw in a lil' global-warming and the edges grow even murkier. The real kicker, though, is that through it all, humans are getting ecologically-dumber by the minute. The divorce between human civilization and the natural world is all but complete. Perhaps I exaggerate . . . but papers have been filed, for sure . . .

     Anyway, for those who do happen to pay attention to the natural world – and let's be succinct and call that world what it truly is: “Reality-with-a-capital-R” – it's cool to have the birds of the air and the plants of the earth around to remind us of what season it is.

White-throated Sparrow, photo by Russ Norwood

     Down at this latitude (about 50 miles north of the Gulf Coast), for example, we should not say that winter is here until the White-throated Sparrow has arrived and settled in. Each winter, White-throated Sparrows occupy just about any shrubby forest edge down here, including properly-arrayed urban and suburban backyards. Really, you don't even have to see them. Like so many other winter birds down here, they are very vocal, uttering their loud, musical, “tEA!” (or “dEE!” or “chEE!” or “pwEE!” depending on your ear...) orientation calls each dawn and dusk; and occasionally breaking out into their mournful “old-Sam-Pea-body” territorial breeding song.

Eastern Towhee, photo by J. Spohrer

     Ditto for other local winter-resident birds, including the Eastern Towhee, that big, handsome “sparrow of the briars.” Generally, towhees prefer wilder settings, so their penetrating, “jREE!” dawn/dusk orientation call is heard only occasionally in urban/suburban forests.


Yellow-rumped Warbler, photo by Russ Norwood

     Birds that breed in North America and overwinter in the Central/South American tropics are known as Neotropical migrants; as opposed to birds that breed to our north and overwinter down here along the Gulf Coast, which are referred to as Nearctic migrants. The most common of the nearctics around these parts include species like Yellow-bellied Sapsucker, American Robin, Cedar Waxwing, Yellow-rumped Warbler, and Ruby-crowned Kinglet.

Eastern Phoebe, photo by Russ Norwood

     Another fairly common local overwinterer is the Eastern Phoebe, a graceful, mockingbird-sized flycatcher. Its drabish colors and relatively sedentary feeding habit often renders it invisible to non-birders; but its loud, reedy, “fee-BEE, fee-BEE” call echos through the woodland habitats (woodlands around water are its absolute favorite) that it frequents.

Nutmeg Hickory (Carya myristiciformes)
26 Nov 2010, Lafayette Parish

     If bird-detection proves too much work, then the local trees fairly shout out in-your-face-style that fall is gone and winter's here. That's right, we do not have much of a fall foliage color show down here. What we do have is a winter fall foliage color show!

American Hornbeam Foliage (Carpinus caroliniana)
26 Nov 2010, Lafayette Parish
   
      It is said that end-of-season foliage color is a product of that tree's metabolic wastes, sequestered in its leaves and visible only after chlorophyll production ceases. As green chlorophyll cells peter out, the oranges, yellows, and reds of these wastes are made manifest.

Sassafras (Sassafras albidum)
07 Oct 2004, probably in n. Illinois
    
     So the situation down here is that in October and the first half of November, our trees are still working – still making and storing food – while trees of the northeastern U.S. and upper-Midwest have thrown in the towel for the year and given up their chlorophyll. The time to start looking around here for foliage color is right around Thanksgiving, at the onset of winter.

Swamp Red Maple (Acer drummondii)
19 Dec 2005, Lafayette Parish

     You say you don't have no winter color? Then get you some! All of the abovementioned trees grow fine down here. Others with notable winter color at our latitude include southern sugar maple (Acer barbatum), Nuttall oak (Quercus texana), overcup oak (Q. lyrata), Shumard oak (Q. shumardii), Mexican plum (Prunus mexicana), black cherry (Prunus serotina), black gum (Nyssa sylvatica), sweet gum (Liquidambar styriciflua), witch hazel (Hamamelis virginica), winged elm (Ulmus alata), cedar elm (U. crassifolia), strawberry bush (Euonymus americana), swamp cyrilla (Cyrilla racemiflora; aka “Titi Bush”), and rusty black-haw viburnum (Viburnum rufidulum).

     Even if you don't have room for any more trees at your place, take a post-Thanksgiving drive to your local woods in late November. You'll see winter color, baby. While you're driving, you may as well continue north to the Interstate-20 corridor, where you'll find Louisiana's finest winter color show. The most easily accessible winter foliage color destination around Shreveport is the Walter B. Jacobs Memorial Nature Park (http://www.caddoparks.com/memorial.cfm). In northeastern Louisiana, my personal all-time state favorite for winter foliage color is the Sicily Island Hills Wildlife Management Area (http://sicilyislandhills.com/).



Tuesday, November 23, 2010

a tale of two cypresses


Cypresses I have known/loved:
Bald cypress (above);
Montezuma cypress (below)


     Back in the early/mid 90s, University of Louisiana-Lafayette student/Acadiana Park Nature Station naturalist Michelle Harper presented me with a seedling of a Montezuma cypress that she had found growing in a greenhouse gutter behind the biology building at ULL. Many moon ago, someone had planted a Montezuma there, and it had grown to massive proportions.

     I duly planted Michelle's gift off of the west wall of our house in an attempt to mitigate the harshness of the summer/afternoon sun against our west wall. I had heard from Texas native plant friends that Montezuma cypress was “kneeless,” as opposed to our native bald cypress, which throws knees left and right, so I plopped it in the ground a mere 8' from the house.

     In relatively short order (ca. 15 years), the Montezuma – a mere toothpick of a plant when Michelle gave it to me – has grown to a height of 70', which is about equal to that of the bald cypress that Lydia and I had planted about 50' away on the north side of our house in 1983! Truly a jack-and-the-beanstalk type situation. Apparently, Montezuma cypress appreciates our swampy, “blackjack” clay as much as bald cypress does.

     The bald cypress ranges natively from the Texas Hill Country east through Florida and north to southern Illinois, whereas the Montezuma cypress is predominately a Mexican species, natively pushing its way north of the Rio Grande only into a few of the southernmost counties of Texas.

     Though half of the foliage is gone on the two late-fall photos (above), you may note that compared to bald cypress, Montezuma cypress possesses a moderately “weepy” foliage habit – perhaps owing to the fact that Montezuma cypress leaves are a tad shorter, and its needles a tad longer, than those of bald cypress.

Bald cypress leaf (left); Montezuma cypress leaf (right)

     Both bald and Montezuma cypresses belong to the cypress family (Cupressaceae), and both belong to the genus Taxodium. Up until recently, bald (Taxodium distichum), pond (Taxodium nutans), and Montezuma (Taxodium mucronatum) cypresses, along with close California relatives coast redwood (Sequoia sempervirens), giant sequoia (Sequoiadendron gigantium), and dawn redwood (Metasequoia glyptostroboides), from China were given their own family (Taxodiaceae); but they have recently been lumped back into Cupressaceae, still a fairly small family, now containing 29 genera and 146 species distributed throughout both hemispheres.

     The story surrounding the dawn redwood is most interesting. It was not discovered (by science, anyway...) until 1944, when a Chinese botanist found a small grove of it – part of a religious shrine, actually – in the Sichuan-Hubei region of that country. The news eventually hit the U.S., and by 1948 Harvard's Arnold Arboretum sent an expedition over to China to collect seed from the tree. Virtually every dawn redwood grown in the U.S. today comes from that original seedlot. Since its initial discovery, dawn redwood has been discovered in only a few other places in China, and is presently listed as “Critically Threatened” in the wild.

     All of these close relatives are known for the huge sizes they attain – redwoods and sequias, up to 300'; dawn redwood, bald and Montezuma cypresses, up to 200'. Do yourself a favor and check out the legendary grand champion Montezuma cypress in the village of Santa Maria del Tule in Oaxaca, Mexico (http://en.wikipedia.org/wiki/Taxodium_mucronatum) – not so tall (ca. 140') but with a trunk diameter approaching 38'! And what about the grand champion bald cypress, located right here in good ol' Louisiana within the Cat Island National Wildlife Refuge in the Mississippi River backwaters just north of St. Francisville (http://www.fws.gov/refuges/profiles/index.cfm?id=43697)? Whoa. Ya'll oughta drive over to see that one. You'll need to make your trip during the dry season, as the site is often flooded under 15' of Mississippi River backwaters.

Yellow-rumped Warbler
(photo by Russ Norwood,
http://www.perceptivist.com/)

     One last note. This fall, when the usual “flocklet” of Yellow-rumped Warblers arrived to overwinter in our yard, I found it interesting that they immediately zipped up into the Montezuma cypress for a foraging session, eschewing all other trees, including the native bald cypress. Of course I have no idea as to what they were hunting for, but apparently the Montezuma had it – or at least more of it – than any of the other trees.

Tuesday, November 16, 2010

what birds eat part II

Female Cardinal . . . where you been?
                                           Photo by Russ Norwood www.perceptivist.com




“Hey me
Hey mama
Where you been?
For so long, For so long?”

                           – Ray LaMontagne
                                             from “Hey Me, Hey Mama”


Blogger note: Besides a couple of photos by long-time naturalist buddy Beth Erwin (curator, Kalorama Nature Preserve, Collinston, LA) and myself, this post features the ultra-fine pics of Baton Rouge ad-man and nature photographer, Russ Norwood. Check out www.perceptivist.com!

     It happens every autumn in backyards all across . . . America? The world? I dunno. All across Louisiana, I know for sure – including here around Lafayette – beginning generally around mid-October (although this fall, not until the first week of November), and usually persisting for the next 6-8 weeks . . . one minute, it's birds galore; and the next minute, BAM! Gone.

     The sudden disappearance of birds – cardinals, chickadees, titmice, mourning doves, woodpeckers, blue jays, chickadees, titmice, cardinals, house finches, etc. in our case – that otherwise spend each and every day crowded around the feeders in one's backyard is dramatic, to say the least. Dramatic enough to be noted by even the most lackadaisical of backyard bird folks.

     So what's the deal? Where have all the birdies gone, long time passing?

     Apparently, no human knows for sure, but conventional wisdom says that backyard birds disappear each fall in response to the ripening of that year's crop of wild seed. Makes sense. Why stick around for stale, non-diverse, store-bought seed when there's a fresh supply of way-diverse wild seed hanging so tantalizingly off of plants just a few wingbeats away? I mean, a bird can return to the ol' seed trough anytime he/she wants; so why not go for the good stuff while the getting's so good?

     Regarding The Great Departure here in the pseudo-wilds of upper Lafayette parish, the backyard silence becomes deafening. Like, wow, so this is what 'quiet' really sounds like, huh? After only about a week or so, though, the chickadees slink back . . . followed a week or so later by the titmice. Apparently, these two species quickly run out of whatever wild stuff out there that happens to trump good ol' black-oil sunflower seeds.

     Of course chickadees and titmice eat far more than black-oil sunflower seeds – all manner of tiny insects, insect eggs, insect larvae, etc. – regardless, they come crawling back home in pretty short order.

Male Cardinal, Kalorama Nature Preserve, Morehouse Parish, LA
photo by Beth Erwin


     The doves, cardinals, and house finches, on the other hand, stay gone the longest; apparently finding far more in the way of wild quality and quantity than do the chickadees and titmice. In the interim, what few cardinals we do notice back in the yard are coming back for water, not seed. Also, we note several of the youngest cardinals sneaking back in each dusk, obviously interested in the safer roost sites they grew up with here around the homestead.

Blue Grosbeak munchin' wild rice at Avery Island 19April2009
                                           photo by Russ Norwood www.perceptivist.com



     Ah, birds and their seeds. So inspiring. What precious little a bird needs to sustain itself, you know? Like, a few grams' worth of seed each day. St. Francis of Assisi (himself known as il povrello, the poor one) spoke of the inspiration that birds provide a person who's looking to live a more simple life.

Field Sparrow, Morehouse Parish, LA 06Nov2010
                      that little hint of a tuft hanging on its bill is leftover little bluestem grass seed
                                                              photo by Beth Erwin


Swamp Sparrow chomping the paint-brush-like seed of boneset (Eupatorium spp.)
                                           photo by Russ Norwood www.perceptivist.com


     I remember the first time witnessing swamp sparrows and American goldfinches devouring goldenrod seed. Tethered to a silken-chute far larger than itself, a goldenrod seed is too tiny for most humans to see or even feel. To a big ol' human, it's just totally amazing that a bird would even bother with it; but bother with it, they do. . .

     Of course most bird species do not limit themselves to a seed-only diet, since seeds are by no means year-round food items out in the wild, particularly up here in the temperate zone. As previously mentioned, small woodland birds such as woodpeckers, chickadees, titmice, and warblers are near-perpetual insect eaters, collectively rummaging through forests like a fine-toothed comb, relieving trees of the bulk of the leaf-eating stem-sucking bugs that annually infest them. What would our forests look like without these little birds? Would we even have forests to look at without them? Legendary wildlife conservationist Aldo Leopold (you must read A Sand County Almanac if you haven't already done so . . . in fact, if you've already done so, then read it again) wrote, “The last word in ignorance is the man who says of an animal, 'What good is it'?”

     As little as humankind thinks of or about tiny, insectivorous birds, would it not be ironic if we were to discover that it is tiny, insectivorous birds which are actually in charge of maintaining the health of the planet's forests? Or at very least, the primary care-givers to the forests?

     One day my buddy Neal Walker called to report that cedar waxwings (probably the most frugivorous of all North American bird species) were picking off aphids who were attracted to the new spring growth of a river birch outside of his kitchen window.

Cedar Waxwings devouring newly emerging blooms of green ash: “spring greens”
                                                         Baton Rouge, LA 12April2009
                                            photo by Russ Norwood www.perceptivist.com

     And it doesn't stop there. Students of bird nutrition soon learn that in their relentless search for calories, it's amazing what some birds gain sustenance from. In early spring, obvious fruit eaters like cedar waxwings, along with such dedicated seed eaters like white-throated sparrows and American goldfinches, can all be seen “getting their spring greens” from newly-sprouted flowers, samaras, etc. of deciduous trees.

Winged Elm samaras (Ulmus alata)...excellent February food for Louisiana sparrows and finches

Baby Common Moorhen learning the joys of duckweed
                                                        Lake Martin, LA 10June2006
                                           photo by Russ Norwood www.perceptivist.com

Prothonotary Warbler, a dedicated insectivore if there ever was one, making off with a black cherry fruit
                           Sherburne Wildlife Management Area, Iberville Parish, LA 15June2008
                                           photo by Russ Norwood www.perceptivist.com

     Obviously, such items are packed not only with calories, but also with minerals and other micro-nutrients that these birds cannot easily procure in their normal fare. Got to get it, Papa!

Wednesday, November 3, 2010

what birds eat

eek! ....... no, yay! ...... a mouse!

     Charles Allen recently forwarded these two great blue heron photos sent to him by Theresa “tay” Lyons from Lake Authur. On the morning of October 23 she photographed the bird as it foraged around her family's grain elevator. It's probable that many of you don't know what great mousers great blue herons are. Ditto for cattle egret. I think herons and egrets in general will down anything 1) that they can catch and 2) that can fit down their gullets.


     If you live over in the ag lands, rice country in particular, you're going to be dealing with mice and rats – mice and rats in such numbers and diversity that regular people could scarcely perceive or imagine.

     Come harvest/post-harvest time, the rodent population duly explodes, and dinner is served – both for the rodents and the rodent-eaters. Due to the uber-high fall/winter rodent population, the diversity and numbers of rodent-eaters which they attract correspondingly rise. Great blue herons and cattle egrets are but the tip of the iceberg. Add in red-tailed hawk, red-shouldered hawk, marsh hawk, cooper's hawk, barn owl, great-horned owl, short-eared owl, mink, raccoon, and yes, coyote, and the iceberg grows. For a fact, the rice country of southwest Louisiana attracts some of the highest winter concentrations of all of the abovementioned, making it an outstanding place and time to view wildlife.


 ring-billed gulls food-freakin' during a ricefield water-leveling operation


many species of sandpipers (including these Least Sandpipers), plovers, and other shorebirds
utilize rice fields during fall, winter, and spring (photo by Dave Patton)

     Add in the dozens and dozens of species of other herons/egrets/ibis, ducks and geese, gulls and terns, sandpipers and other shorebirds attracted to the aquatic life of winter-flooded rice fields; as well another few dozen species of wrens, warblers, sparrows, and other songbirds that secret themselves in the dense hedgrows around irrigation canals and field edges and you've got a real smorgasboard of bird life happening. I once saw a belted kingfisher, perched happily up on a utility wire adjacent to a rice field – with a medium sized crawfish flailing in its bill. Many of you non-rice farmers/crawfishermen would be shocked at the number of bird species that routinely utilize crawfish in their diets.


Barred Owl basks after successful fishing trip
 photographer either Dave Patton or Stacey Scarce...or somebody else.....

     I've got a billion winter rice field stories, but of my favorites involves a pair of coyotes that I watched for an entire cold, sunless December afternoon behind Paul and Darnelle McIntosh's northern Vermilion parish home. There in a large rice field complex, they were stalking mice and rats along the narrow, brushy levees stitched throughout the rice fields. Carefully creeping and sniffing, they worked as a team, pouncing high like buckin' broncos onto the poor rodents they'd find.

     I've had a quasi-obsessive interest in food habits of animals – especially birds – for a long time now. Maybe it's because I've taken the time to learn to identify both animals and vegetation (alas, many birders choose to remain oblivious to the identity of the non-bird animals and plants they are constantly encountering in the field; likewise for plant-lovers on their field trips). Maybe it's just because I love food.



                                                                     Birds 'n Berries


Eastern Bluebird with native viburnum fruit, Dauphin Island, AL, 17 Oct 2010
photo by Dave Cagnolatti


     At the behest of an ornithologist friend, I coordinated a five-year Survey of Bird Frugivory in Louisiana (Journal of La. Ornithology Vol. 4 No. 2, Winter 1998). Frugivory is the act of eating fleshy fruits such as blueberries, hollies, cherries. Together with 25 other field observers, we amassed a database of over 1,000 bird/fruit observations involving 67 bird species which were observed consuming some 57 species of fruits (mostly native).


red-bellied woodpecker eating wild hawthorn fruits
photo by Beth Erwin

     Probably half of the observations were of the “expected” variety, such as robins and cedar waxwings eating holly fruits, or mockingbirds eating elderberries. On the other hand, I think that all of us were uniformly surprised at the degree of frugivory exhibited by woodpeckers. In all, we recorded 7 species of woodpeckers eating all manner of fruits including persimmon, black cherry, sumac, mulberry, dogwood, and many more.

     Another surprise involved the degree of frugivory exhibited by flycatchers, particularly during the fall migration period (July-Oct), in which they focused on two plant species in particular: prickly ash (Zanthoxylum clava-herculis) and rough-leaf dogwood (Cornus drummondii); and were also substantially interested in bird pepper (Capsicum annuum glaberisculum).

     In terms of diversity of bird species attracted, know what the all-time best plants were? King of 'em all was hackberry (Celtis laevigata), followed closely by Virginia creeper (Parthenocissus quinquefolia), and . . . (drum roll) . . . poison ivy. Yep. Poison ivy berries proved attractive to not only the typically frugivorous species like robins and mockingbirds, but also several species each of woodpeckers, warblers, and sparrows, not to mention chickadees, titmice, kinglets, and others.


evil poison ivy (note tiny berries in back)...wanna know what it's good for? ask just about any bird or mammal....
photo by James Beck

     Other high-scoring plants included black cherry, red mulberry, elderberry, pokeberry, southern magnolia, wax myrtle, and black gum.