Dicromantispa interrupta

Dicromantispa interrupta

Friday, February 26, 2010

I am a Torreya Guardian

I first heard about the world’s most endangered coniferous tree, the Florida torreya (Torreya taxifolia) while taking a tree identification course in college in the late 1960s. This species had been reduced in the wild to a few Apalachicola River tributary ravine habitats, which Torreya State Park had been created to include. It was hoped that the species could make a last stand there and, hopefully under state protection, become re-established as a viable population. I have visited that park a few times but have seen no evidence that the Florida torreya is rebounding therein. The last time I walked some of the wilder ravines in the park, all the specimens encountered were small and severely grazed by deer or used by bucks to scrape the velvet off their antlers. None of these plants were receiving any protection whatsoever from deer or other wildlife, and I got the distinct impression that they were doomed by browsers and official inattention.

But this was not always the case. Early botanists described the tree as a prominent mid- and under-story species growing along a 65-km stretch of the Apalachicola River and up its tributaries, achieving up to a meter in circumference and 20 meters in height. A still-unexplained “catastrophe” in the 1950s, however, laid waste to the plants, so now there are only stump and root sprouts within its historic range. It is reminiscent of the chestnut blight, and a similar fungal pathogen is thought to be the culprit although little research into the cause has been done.

Over the years, I have discussed this situation with some of my naturalist friends. All who have seen the torreyas on the state park agree that it is a sad situation and are resigned to losing the species in the long run. I often asked why could we not artificially propagate it and plant it more abundantly within and outside of the state park. Most responses were glass-half-empty statements that need not be repeated, but some of my comrades had the curious, quasi-religious belief that if it didn’t already grow elsewhere then it shouldn’t be planted elsewhere! One fellow actually stated, “If it was meant to be there, it would already be there.” I was astounded at this attitude, but this mentality evidently holds sway over the state park system in regards to the Florida torreya. For shame!

It has been proposed that the Florida torreya might have become “trapped” in a Florida peak-glacial pocket and is unable to naturally re-expand northward into cooler climes, which it possibly prefers as a consequence of the absence of a co-evolved seed disperser. I am not inclined to believe in the seed-disperser hypothesis, though, as squirrels assiduously seek out torreya seeds and eat and presumably cache them, and because the species was propagating itself quite nicely before the 1950s. Fortunately, it has been artificially propagated successfully at the Biltmore Estate in North Carolina and at the Atlanta Botanical Garden. I have seen the Biltmore trees; they are truly beautiful, dark glossy evergreens and I have wanted one ever since.

About a year ago, I read of the Torreya Guardians (http://www.torreyaguardians.org/). This group of dedicated individuals has determined that the species will probably go extinct under current public management policies. Deeming this unacceptable, they have assembled unofficially (no membership roll, no dues and no officers) in the private sector to try to bring the species back from the brink of extinction. They have done quite a lot of research on its propagation requirements, both from cuttings and seeds obtained from Biltmore and Atlanta, and hope to re-establish it within its theoretical cooler-climate range outside of Florida.

As I own a 2-acre lot in the mountains a few miles from Biltmore and (ahem) have a green thumb and a jones for biodiversity, I contacted them asking if they could spare me a few seeds. After many months, they responded with an offer of 10 seeds! But they want me to propagate them in Florida rather than North Carolina because they want to learn whether the species can live in Florida in places other than Torreya State Park. Wow! I am just so excited that I can hardly stand it! I received the seeds today and promptly set them out according to their recommendations. I am now a Torreya Guardian.

Waccasassa Winter

I went kayaking with Jim and Brack yesterday on the Waccasassa River in Levy County, FL. Brack and I became acquainted with Jim by virtue of him being a reader of my blog. As mentioned in the sidebar, one goal of this blog is to meet fellow naturalists from around the country (world), and it was a real pleasure to spend some time in a fine Florida floodplain with another naturalist from a different part of the country - New York, in his case. So, to the rest of y’all: Come on down!

We put in at the boat ramp at the end of CR326 and paddled upstream. It was right cold, too, maybe in the 40s with a perky little breeze, but we were dressed for it with long johns and neoprene socks. Brack’s kayaks are stable and drain splash water quickly, so the only parts of me that got wet were my ankles, and they were only moistened. We left the boat ramp about 10:30am and returned at about 3:30pm, an easy 5-hour loaf.

Passing by the mouth of the Wekiva River, we noted its dark, tannin-stained waters. Ordinarily, this spring-fed tributary’s waters are clear to the bottom and its thick submerged vegetation is clearly visible. Winter rains have swollen the basin’s wetlands and streams, however, carrying heavy loads of leaves and other detritus that contribute dark-colored compounds and particles into the waters. At one point, I tried to shove off a “sandbar” covered with leaves by pushing against it with the paddle, but it just sunk in about 18 inches, proving that the bar was really just a manatee-sized leaf pack. Despite the high waters in the tribs, the river’s level was down due to it being at low tide and close to the sea. Although the current was swift in its shallower reaches, our kayaks slipped easily over the river’s flexed muscles.

Tidal riverbanks and salt marshes are muddy. You almost cannot get in and out of your kayak or canoe without getting muddy feet. Nonetheless, the banks in tidal waters seem to avoid eroding away despite numerous fiddler crab holes and swift currents. Now how can this be? This photo gives you some idea of how algae can provide armor against erosion. The depicted algal mat (the laurel oak leaves in the photo are 2-3 inches long) is filamentous and grows on top of the mud. It is apparent why it can retard erosion, but most mud banks are not so well-protected. Instead, the upper eighth-inch or so of the mud is perfused with thinner, less-visible filaments of algae that enmesh it all together. Jim likened it to a web of fungal hyphae, and upon reflection, I wonder if fungi are also associated with this wetland substrate?

For me, one of the nicest things about Florida is that you can find flowers during any month of the year. Only a few species of wildflowers were blooming yesterday, being common blue violet (Viola sororia), butterweed (Packera glabella) and golden club (Orontium aquaticum), and only one kind of shrub, Walter’s viburnum (V. obovatum). Red buckeye, wax myrtle and swamp privet (the native Forestiera acuminata, not an invasive exotic Ligustrum) exhibited flower buds, but they were not quite yet open for business. Wind-pollinated, leafless trees on the other hand, were starting to bloom pretty good, including sweetgum, winged elm, red maple, bald cypress and coastal plain willow, and possibly others too tall to clearly tell. Fortunately, the oaks and pines were not yet trying to ignite hay fever inflammations.

Where the river passes under CR326, two of the pilings holding the bridge up were badly eroded by physical damage and corrosion. Here is a photo of the worst one, with its reinforcing wires fully exposed! One wonders how many pilings are actually necessary to support this bridge, but I suppose FDOT has made the county build in sufficient redundancy.

Not surprisingly for those who know me, we just had to stop by the solution valley located up one of the Waccasassa’s tributaries that I have mentioned here before. As you may know, a solution valley starts out as a limestone cave whose stream floor has become an above-ground creek because the roof of the cave has eroded away. In this case, remnant side passages still exist, so the big picture is that of a system of little caves pointing toward a small brook. Below are several pics of the system. In one shot of a cavern entrance, you can see the reflection of water lit from behind. In another shot, Brack demonstrates how small these cave entrances are. Most of these holes are too tiny for designation as caves by the Florida Cave Survey, and in several instances are more properly considered natural bridges. All are quite wet and muddy, and there are a lot of natural bridges, too. Also pictured below is cretan brake fern, Pteris cretica. It has the odd distribution of being known in the US only from Florida, Maryland, Louisiana and California.

Saturday, February 20, 2010

Winter in Warrens Cave

It has been a while since I have been in a Florida cave. No particular reason, just haven’t. Dave L invited me to join a few adventurers at Warrens Cave on Friday evening, so I was thankfully able to get a speleofix and end my speleodrought. The six of us actually comprised two teams: Alex, Mike and Chris wanted to zip back to the Sand Room and Dave, another Mike and I to go a little more slowly to the Sand Room. Bill Oldacre, the property manager and fellow that is responsible for Warrens Cave being under caver management, met us at the gate on the dirt entrance road with the two keys to the road and cave gates. It is always good to visit with Bill, but this time it was especially gratifying as he presented me with a couple of gifts in recognition of my small contributions to the NSS Nature Preserves (Warrens is one of thirteen) as former Chairman of the Nature Preserves Committee.

The zip team, a young crew ranging 18 to maybe 24 yo, scooted off ahead, unlocked the cave gate and disappeared. Dave, Mike and I, the more mature (in years only, I hasten to add) team, progressed a little more slowly. Alex is working with Sarah C and Corey B to try to set up a far camp beyond Agony Alley in the very back of the cave in order to extend the known reaches of this, the longest known air-filled cave in Florida. They are all slender, athletic, hard-core(y) cavers, and if anyone can do it, it is they. For those unfamiliar with the situation: Agony Alley is 600 ft of body tube that most of us cannot turn around in, so tight that you must tie your pack to your foot and push your helmet ahead of you, take at least a gallon of drinking water and hope to Oztotl that you don’t get “corked in” by an expiring caver between you and the entrance. I have been back there only once, at a time that I was out of shape, dehydrated, improperly bulked up carbohydratedly and not yet having taken up stamina pills (foxglove). I will never return to those far reaches, but I can proudly say, duh, that I have surveyed passage back there (with Keith S and Bob N). The trip back there is through the Sand Room, noted for its sandpaper-like sediments that can rub your elbows raw, and takes 4 – 6 hours one-way depending on your abilities and physical condition. Alex, Sarah and Corey plan to spend several days on their expedition, and it could go down in Florida caving annals as one of the most grueling ever.

Along the way, we eyed a bunch of small traps that a graduate student has emplaced to capture a tiny species of cave beetle. This beetle is appx 2-3 mm long, less than 1 mm wide and is typically found in the cave on feces deposited by cotton mice (Peromyscus gossypinus). The mice are found almost anywhere cavers frequently go in the cave, eating crumbs left by snackers and probably other types of food washed into the cave during rain events. Cotton mice will also gnaw on ropes and rope backup straps if salty sweat is left on them by riggers, so we must be careful when rigging and using the ropes.

I counted 31 bats in the Historic Section, more than I have ever seen in Warrens at a single time, say hallelujah! They were mostly the Southeastern myotis (Myotis austroriparius) and a few tri-colored bats (Perimyotis subflaveus) (formerly called the pipistrelle, Pipistrellus subflaveus). They occurred on walls, typically immediately below minor horizontal rock ridges or small overhangs, in ones and twos, although I spotted one foursome and one sixsome. In warmer months the cave gate serves as a perch for yellow rat snakes (Elaphe obsoleta quadrivittata), from which they snag and eat bats flying to and from the cave. I would like to see the existing cave gate replaced with one that is more bat-friendly. Although in winters past I have seen rat snakes up to a couple hundred feet inside the cave staying warm, we saw none this time. That’s a good thing for the bats, but last night it was a good thing for the snakes, too, as I had already decided that, henceforth, I am going to capture and relocate all rat snakes I find in this cave. This is not ordinarily considered a cool thing to do, but bats are under many serious threats, especially at Warrens, whereas the yellow rat snake may be Florida’s most common large snake. I don’t know if there is such a thing as a homing snake, but I bet they will be hard pressed to re-find Warrens after being relocated to the trees beside Orange Lake.

I found myself commenting twice during the trip that the most important rule about caving is to know your own limitations, not in lecture but because it was already ingrained in my companions and they knew when to exercise the rule. Kudos!

Friday, February 12, 2010

Ketch dogs and bay dogs

There are ranches and there are ranches. Some are lived on and operated by affluent owners and others are occupied and run by low-paid, uneducated hired managers. The worst are hired louts that act like barbarians, cruel to the bone. One such fellow I met gave me an education about rednecks hunting feral pigs, and it is everything a sensitive human being could dread.

They have “bay dogs” and “ketch dogs.” He says ketch dogs (you and I would say, “catch dogs”) are a “dime a dozen,” and talks about them like they are throwaway appliances. A ketch dog will hit the trail to sniff out a pig, follow the scent trail to the pig and then clamp down on the victim with its powerful pit bull jaws. This is quite painful for the pig, duh, which commences to squealing mightily. Believe me, it is an awful, heart-wrenching sound. The pig tries to throw the dog off, but a toothy dog-vise cannot be slipped. The pig tries anyway, slamming the dog around brush, briars, rocks and trees, and occasionally the pig’s “tushes,” or tusks and hooves meet dog meat too. The damage to the ketch dog can be so severe that it has to be killed. Why take the appliance to the vet and spend a few hundred dollars healing it when it costs only twenty-five bucks to get another? They just shoot ‘em and leave ‘em in the woods for vultures and ‘possums.

The bay dog is another matter. Dogs so want to attack the pig in the heat of the hunt when another dog is attacking the porker, but that is not allowed to bay dogs. You see, the job of the bay dog is to follow the ketch dog, perhaps even help sniff out the trail, and then bay (howl) loudly and constantly until the hunter reaches the trio and shoots or spears the pig (and maybe the ketch dog). If the bay dog attacks the pig, the bay dog could get hurt and not be able to tell the hunter where the trio is located, so breeders train bay dogs not to attack. As I said, it is hard to train a dog to sit back and let the ketch dog have all the fun, so bay dogs go for up to a thousand dollars each, and if you sell a redneck a bay dog that attacks pigs, you can expect to have to give the barbarian his money back and take a lot of heat, too. At this point I should point out that my informant has prison tattoos on his knuckles and says that he had to quit drinking because his “personality changes when [he] drink[s].”

These dogs are kept in small pens way out back away from the house, not so far away that they cannot be heard barking and howling all day long and some of the night too, just far enough away that you can’t smell the stench of dog feces from the back porch. The dogs are not allowed physical contact with each other despite their being highly social animals. They cannot touch or groom each other, as they want to do, cannot establish a pecking order as they need to do and cannot play together as their intelligent brains insist they should do. They cannot get out and run and run and run as a long distance running animal is built to do, so when they are let out to hunt they tire easily, get hurt easily and get lost and sometimes killed by predators and starvation. Of course, being done in winter, lost hunting dogs also have to face the cold and sometimes the rain, too. Their pens are extremely small, generally less than 6ft x 6ft, so they cannot even pace about to maintain muscle tone. They defecate and urinate on the floor that they sleep on, and the feces are simply hosed out every week or so, resulting in a very stinky environment. Nor do their owners offer them any affection or attention (surprise!).

These rednecks care not a whit for any but their bay dogs, and them only because of the expense. When I look into the eyes of these penned dogs, I see misery, plus hopelessness in the older dogs and pleading in the younger. Why is this cruelty allowed? I simply cannot understand why the authorities do not put a stop to this egregious inhumaneness. Surely, this is illegal under any animal cruelty law or ordinance? Why is this butcherous behavior tolerated by the ASPCA, PETA and animal control organizations?

But let’s get back to the pigs. Anyone who reads this blog knows how much I despise feral pigs due to their significant, adverse impacts to native vegetation and wildlife. I would like to see feral pigs eliminated from the US by the use of traps and euthanasia or by well-placed gunshots, but not by cruel means. My informant has other ideas. After trapping young boars, he breaks off their upper canines with pliers so their lower canines will grow longer and be more impressive as a wall mount, and so the dogs and hunters are less likely to get injured. Then he cuts off their testicles so they will grow larger and taste less rangy. He will sell the large boars to hunting concessions for a hundred dollars, where they will be hunted as described above. Smaller pigs will be sold to hunting concessions for “meat hunting” at a rate of twenty-five dollars, and these too will be hunted but not wall mounted. Many older sows will be released so’s they can reproduce. He will relocate some sows and small “uncut” boars to places that “don’t have enough hawgs.” By the way, this latter is one of the main reasons that the Florida Fish and Wildlife Conservation Commission ceased offering bounties for feral pigs. They learned to their dismay that rednecks were deliberately releasing pigs on state lands so there would be more to hunt there and nearby!

As I said in a previous post, Okeechobee is culturally grim.

Tuesday, February 9, 2010

The Caracara and the Wild Man

One pair of caracaras almost drove me nuts trying to find their 2010 nest. Their 2009 nest was a single palm in open pasture away from a marsh. The tree having no lianas and only a few inflorescences to anchor it, winter winds had shredded the nest and the birds did not repair it. I don’t blame them for moving, but wonder why they chose that particular tree in the first place? Maybe they are a relatively young pair and it was their first nest, or maybe I just don’t know enough about caracaras.

The 2009 nest wasn’t very close to a favored perch – a half-dead pine – but the pine was adjacent to a small marsh and was probably a good perch to hunt from in 2009 because then it was wetter and produced more prey. The marsh is dry this year; in fact, all the marshes anywhere close to their 2009 nest are dry so far this year. Nonetheless, this pine is still used occasionally by the pair and is where I first saw them, and thus subconsciously I concluded that it was a good place from which to follow them. Wrong! They all but stopped perching there after I started looking for their nest.

On Day Two, they began flying from somewhere in the east, passing over the pine perch and landing in a pine snag to the west. I walked over there and spied a disheveled stick nest in the snag, definitely not a caracara’s, but it didn’t look active. Possibly the caracaras had a nest in one of the nearby palms? But the caracaras didn’t spend much time there. They just went over briefly and then went to some place in the east, again and again. It turned out that a pair of ospreys were actively building that nest and the caracaras didn’t like it one bit. But one osprey can run off a pair of caracaras, so perhaps the osprey were one of the reasons the caracaras moved their nest?

I walked over to the east side of the territory where I thought they were coming from and found what seemed to be a fine spot for a nest. It had several snags offering commanding views, a larger (albeit dry) marsh and a palm with the right amount of lianas and inflorescences (a liana is a woody vine). But there was no nest there. At this point, I had also sat hidden and quiet for several hours in each of several places watching for caracaras to see where they came and went, hoping that they would reveal the location of their core territory. A core area is where the nest, one or more high perches and a nearby dependable source of food are co-located and competitor core areas are distant. Once you find the core area, you hang out and you will inevitably find the nest. I walked all over their territory over a second half-day looking for activity that would lead me to their core area, all to no avail.

Near the end of that day, when the caracaras were gone I snuck over to a palm hammock that gave a view of the old nest, a potential nest tree and a flyway they had used repeatedly to launch harassment attacks on the ospreys. I waited and waited but saw nothing, so decided to move. At about official sundown, I snuck carefully and quietly around the edge of the hammock to a second observation post, spadefooted my way backwards into a dense clump of tall grass where I believed I was well-hidden, and looked up into the bemused eyes of the male caracara sitting on a fencepost about 100 ft in front of me, and got that old flush-cheeked feeling again. You know how it is when you’re busted but you bravely bluff your way through just in case your opponent doesn’t care? Well, that’s what I did. “Ok, you spotted me,” I thought, “so what are you going to do about it? You still have to go to bed tonight, and I’m not leaving until after your bedtime.” He answered by leaping off the fencepost flying straight toward me, and then banked to his left and rocketed away along the tree line. Care to guess whether he lost me?

The next day, I noticed them headed a little south of “the” east that I had investigated earlier. Following up, they proved to be using power poles and an oak for core area perches a lot closer than the east area. “Ahah,” I thought, “all I have to do now is look at all the cabbage palms in there and I’ll for sure locate the nest.” But all the cabbages in their core area are tall (at least for South Florida), easily 70 – 80 ft, which makes it very hard to discern nests in trees containing arboreal thickets. I looked and looked, yet could not find the nest. I sat down in the shade of a bush and waited for them to show it to me even though they knew I was watching. That evening they pulled the standard tricks of male-decoying-me-so-female-can-sneak-into-nest (which worked) and right-at-dark-male-zips-into-nest-from-fifth-dimension (which also worked).

The next day I waited until both birds left the core area. I was just about to run over to a pre-selected, hidden observation post, but just then, the female came back. Fortunately, she immediately dropped down out of sight right over there, so I thought that if I ran as fast as I could that perhaps I could get under cover behind the barn before she flew up to where she could see me. I did and she didn’t – good so far. She had landed on a utility pole behind the landowner’s house, and from there she flew over to the nest tree. I didn’t know it was the nest tree at the time because I had already looked for a nest in that tree without finding one, plus she was sitting way out on an inflorescence outside of the crown’s foliage instead of hiding inside the crown. She sat there for awhile, flew down to the ground where I couldn’t see her, flew up into a second palm and sat on one of its inflorescences, and then a few minutes later flew off to the east. I knew either of those two palms might well be the tree.

This was good and this was bad. It was good because the area was open and everything was easy to see, plus there were good hiding places from which to observe the birds. It was bad because I would have to lurk around the edge of the pasture immediately adjacent to the landowner’s back yard and hide in clumps of vegetation. If their kid happened by and spotted me, it would probably would have been ok because kids are cool, but if poppa was an angry man and happened by…? Oh, the horror… Because I had been trying to not bother them and had not even met them, I really didn’t want to greet them accidentally at that hour, but I had been working on this nest too long, I was in the right place at the right time and no one seemed interested in visiting the pasture, so I blessed my camo and proceeded. Call me a wild man.

I knew the female caracara would go to the nest well before official sundown, perhaps by an hour or more. I had maybe 1.5 hrs before sunset, so I ran over to the hammock that was close to the two potential nest trees that she had shown me. I found a hiding spot at the edge of the body of the hammock and waited. I didn’t like that spot so moved to another that was on the tip of a point of the hammock, more exposed to humans but still well hidden from caracaras. The two birds returned to core perches before long and gave no indication that they were aware of my presence. The pair left again and I used that opportunity to move quickly to yet another post, closer to the perches and the presumed nest trees, but even more exposed to wandering landowners. When the birds returned I discovered that a critical part of my view was blocked by vegetation, so when they left again I moved to yet a fourth, even more exposed yet still well-hidden spot. I felt like an accomplished sniper when they returned unsuspecting. About 10 minutes before official sundown the male flew off and when I looked back the female had vanished. I did not see her again that day. Old trick.

Shortly, the male flew back to the utility pole and at 19 minutes after official sundown, he flew to the nest tree. To confirm that it was the nest tree I walked over and used my presence to cause him to fly away from the tree, because if he returned I could be almost certain that it was indeed the nest tree. The poor fellow couldn’t see me until I was almost directly underneath him due to the darkness, and when he realized I was there the expression on his face was absolutely priceless. He was open-mouthed and his demeanor fairly shouted, “Where in Hades did YOU come from!” When I left the tree, he was so anxious to return to it that almost as soon as I turned my back he flew in. This time it was he who was busted, I gleefully note.

There is so much at stake that we have to be extra careful that we finger the correct tree, so I returned the following morning to visually confirm that there was indeed a nest in the tree and that they weren’t just spending the night in a plain old palm. The nest was so new and threadbare that I could see her plainly through the bottom of it, not at all like my earlier post on the usual thickness and opaqueness of their nests.

Finding this nest was a lengthy challenge – it’s a good thing that I wasn’t being paid on a lump sum basis!

Saturday, February 6, 2010

Caracara Nest and Nest Tree

When I first learned last year that I was going to be looking for nests of the crested caracara in South Florida, I reviewed information available on the internet about their nests and nest trees. I wanted to know what I was supposed to be looking for in terms of what species of trees, how high off the ground, construction materials, microhabitat, and anything else that might be pertinent. I learned that caracaras make their nests in cabbage palms 97% of the time in Florida (saguaro cactus in Arizona), but could find no real verbiage on the flavor of the palm or its nest. This post seeks to partially rectify that situation. I have seen a couple of dozen caracara nests by now, not very many by any means, but there are consistencies in what I am seeing that might benefit others. At any rate, the information in this post is more than I could easily find on the internet elsewhere.

Most nest palms are within small groups of one to eight palms and are rarely at the edges of or within large hammocks. It is believed this enables caracaras to have almost unrestricted vision all around the nest tree so that they may better keep a vigil for predators and prey. The typical nest tree is close to several good perches, preferably snags (dead trees), but they will sit in the canopies of living trees if acceptable snags are in short supply. The nest tree is often close to a freshwater pond or marsh so that adults do not have to travel far to get food for mates and young. This photo shows a typical nest site, with the nest being in one of three adjacent palms, two more solo palms in the near distance, and a nearby snag and pine with commanding views. The closest palm contains the nest.

The canopy of the tree will often have a single "landing gap" facing a clear flyway that the birds use to enter and exit the nest canopy. Interestingly, the palm frond on which it perches does not suddenly shake when an adult launches itself from the palm canopy, Even when I watched the nest tree intently, a caracara will seem to suddenly appear out of thin air from behind the tree rather than leave a shaking limb in its wake. This may be a way to avoid giving away its nest to a predator.

The nest tree will not have petiole “boots” still in place from the ground up, presumably so that snakes and other predators cannot easily ascend and attack eggs and nestlings. The tree will have one to several lianas (woody vines), but they will not bush out along the trunk and create a ladder for interlopers. The net effect is a smooth and clean trunk that frustrates nest predators .The tree will be old enough that it has several year’s worth of dried inflorescences still firmly attached and emerging beyond the canopy. Lianas climb the inflorescences and “bush out,” thus creating a “rat’s nest” of tangled vegetation that is large and dense enough that a medium-sized bird nest cannot be easily seen from the ground. Caracaras will tamp down the tangle to make it flat on top and will then augment the platform with dried vines and cabbage palm “socks.”

What are cabbage palm boots and socks? Look at the picture below of a relatively young cabbage palm, noticing on the ground the three Y-shaped thingies and the mass of light brown fibrous material. The Y-shaped boot is the basal part of the palm frond petiole (leaf “stem”) that attaches the palm leaf to the trunk. A few months after a cabbage palm leaf dies it will break off a short distance away from the trunk leaving the boot firmly attached to the tree. When looking at a bunch of cabbage palms, you will often notice that some palms retain their boots and others do not. Evidently, the palms must reach some threshold height or age, or something, before the boots drop off. The fibrous material is produced along the margins of the boots, but by the time the boot falls off the tree, the fibrous material has long since rotted away. For the caracara to use these fibers, it must pick at them when they are alive and tough, near the top of the tree.

Florida Crackers have been calling Y-shaped frond bases “boots” for a long time. I may have independently invented the use of the word “socks” to apply to the basal fibers (socks go with boots, right?), but it’s such an obvious connection that I bet it’s been made before.

In addition to the vines and flower stalks, caracaras weave slender, supple pieces of vegetation and plastic into the nest. The vegetation used seems to be primarily greenbriar (Smilax spp.) stems, but only the very thin, wiry ones with tiny spines. They will also use grasses and stems from other vine species. One nest examined contained black plastic strapping and orange plastic packing twine, and another nest had a piece of red plastic surveyors flagging waving in the wind. In all the cases I have seen, however, nest materials were slender and supple rather than stout and stiff.

Especially interesting is that the adults weave a tightly packed pad of palm sock material appx 10 to 12 inches in diameter and 3 to 5 inches thick into the top-center of the nest. This not only provides a soft, insulating substrate for family, but also is gentler on the bare bottoms of incubating adults and  nestlings. This pic below shows a downed nest that gives you some idea of the overall size, 2.5 – 3 feet in diameter, plus the sock pad (broken up).

As the palm grows upward and its lower fronds die and fall off, attached lower portions of large nests will break away and fall to the ground. If a nest is used every year for several years, it will look like a column of debris extending vertically through the canopy fronds. Sometimes the column will be 4 - 4 feet in height, but most nests I have seen are not so fully-developed. I imagine that as the nest ages and settles, mold and parasites might make it uninhabitable. This is a likely explanation of why they use a nest for only a year or two, and move around among several nests over the years.

The tree may have a very few bird droppings under it because they release most of their feces elsewhere. Favored snags and the ground underneath are sometimes spattered with droppings and may the have remains of food items scattered about. Armored catfish, cattle egret feathers, and miscellaneous bones are frequently found. Oddly, this caracara eggshell was found under an active nest. Ordinarily an adult would remove the egg from the area of the nest.

The caracara is careful in other ways to keep the secret of the nest location. The male and female do not enter the nest at the same time, so predators don’t get a quick second look. They tend to enter the nest fast and from a cryptic route. They will rarely enter a nest if they know someone is watching. At day’s end, they have a neat trick or two to fool you. If both are out of the nest but close by appx an hour before sunset and well before nocturnal predators some out to hunt, the male will suddenly leap off his perch and fly in plain sight only a few dozens of feet from you and tear then outta there fast! You will get excited and jump up and run to follow it with binoculars to see where it goes, but it quickly flies behind a tree line and is lost from view. You look back to the perch to see what the female is doing, but she is gone, vanished. You realize you’ve been had. She snuck into the nest while the male decoyed you away! Now the male needs to get into the nest without being seen. He returns, and if you are still there and he sees you, he has another trick up his sleeve. He waits until about 10 to 15 minutes after official sunset, when there is just enough light to fly by, and then he suddenly launches and flies off again. Again, you jump up and run to where you can get a clearer view of his flight path, but he rounds a corner and is gone. You don’t realize it until it is too late that he is flying a circuitous route to land on the other side of the nest tree canopy.

How do I, the professional wildlifer overcome these diabolical stratagems? Stay tuned, because evolution has prepared me, too…

Monday, February 1, 2010

Caracaras and other Road Raptors

I have returned to working full-time on the pipeline job that I had most of last year doing imperiled species work. I am staying in Lake Placid, FL and wishing there were some good restaurants here. I work as far afield as the other side of the city of Okeechobee (“Oh, Ah’m proud to be an Okee from Lake Chobee…”), and they don’t have any good restaurants, either. At least they aren’t expensive, but I can tell you, my friends, it is grim here, culturally speaking.

But the wildlife is anything but boring. Ranchers down here like to tell me that they have a lot of wildlife, but I want to tell them that they don’t, either, it just looks like they do. Ranches are mostly barren of trees and shrubs, so wildlife can’t hide very well. You can look out over a large field and see whatever lives out there pretty much as plain as day, and you might see a flock of turkeys, a few soaring raptors, feral pigs and armadillos, but mostly what you see is cattle. Ranches do not have a lot of wildlife and they do not have a lot of species, but at least their openness makes my job easier.

I am checking on all the nests of the crested caracara that we found last year to see if they are in use again this year. If so, I mark it down and move on. If not, well then why not? Has the pair moved to another site? We know about one pair that has nested in three places in as many years. Or have they just not yet started nesting for this breeding season? But other caracaras are nesting already, so that cannot be it. Or can it? Maybe some territories are not ready for caracara breeding. Maybe there isn’t enough food for some of them to successfully breed this year?

South Florida’s upland fields are typically dormant and brown right now at the beginning of the nesting season, so there are few grasshoppers and no reptiles to hunt. Caracaras cannot ordinarily make effective use of small upland mammals because those are nocturnal whereas caracaras are diurnal. Only when nights are so cold that rabbits and rodents will forage in the late afternoon when there is still good light can caracaras get some of that. Oh, you want to know why caracaras have such long legs? Last year, one of our team members watched a caracara run down and kill a young rabbit! Those long legs also give the bird a leg up to see above the native prairie and exotic pasture grasses.

Last year at this time, freshwater marshes had water and prey items for the hungry caracaras and their nestlings. Last year there were plenty of frogs, snakes, turtles and fishes in the shallow marshes and ditches, but this year the marshes are all but dried up and have been for months. Cattle have so heavily grazed the marshes that either there is almost no greenery at all in them or only coarse, unpalatable graminoids like soft rush and sand cordgrass. There are no frogs, no reptiles and no fishes in well over 90% of the marsh acreage that was inundated last year.

Uplands do have another prey item available, but I do not know whether caracaras go after them. The fields are chock full ‘o meadowlarks, the males standing decoy with their bright yellow breasts while females hide on their nests in the laid-over cut grass. I have several times watched caracaras walk slowly, zig-zagging through the grass, watching to either side as they go to see what they might flush, but have not yet seen them capture anything.

There is plenty of carrion on the highway for them to eat. I counted five road-killed otters, a dog, a striped skunk, a deer and innumerable opossums and raccoons over the last two weeks. But there is a lot of competition for that carrion, too. Did I ever tell you about “Road Raptors?” This is what I call the group of black bird species that patrol the highways for fresh meat in a predictable manner first thing in the morning. Just as soon as you can see 10ft in front of your nose, the crows (American and fish) and “blackbirds” (common grackle, redwing blackbird, Brewer’s blackbird) hit the pavement looking for small things to eat, like insects and pieces of meat ripped off corpses by mud tires. When you can see 50ft in front of yourself, out come the bald eagles and caracaras. Next is the turkey vulture and last is the black vulture. So, the small road raptors get the really easy pickings, then the caracara and eagle face off over the meat, then the turkey vulture arrives and squabbles with the eagle and caracara, and then the black vultures arrive en masse and run everybody else off. Then the fire ants find the meat and run off even the black vultures! Oh, and the cars. Often I will see birds trying to snatch carrionnettes between vehicles, and remember this is rush hour and it might be foggy too. A few days ago, I spotted two juvenal caracaras dodging hurtling irons, so I pulled over and dragged the (raccoon) carcass off the road.

All in all, I believe the caracaras may not get as much prey this year as in wetter years because of the effective loss of wetland marsh habitats. If so, then there is a good possibility that many of last year’s caracara nesting pairs may not reproduce this year. It was hard enough to find the nests that existed last year, but it is going to be much harder this year if we have to look for nests that aren’t there. On the other hand, if nesting this year is successful overall despite continued drought, it will tell me a sad something about the nursery power of the highway.

And there are other complications. One pair of caracaras nested close to a road in 2009, but that nest had been abandoned and was almost totally gone when I checked it this year. I continued my walk on the mile-square property, inspecting every cabbage palm along the way and discovered the nest they had built for this year. But looking closer, a familiar furry body could be seen in the nest and it wasn’t a bird – it was a raccoon. Either the ‘coon had run off the caracaras, and hopefully they won’t come back and lay eggs where the raccoon can easily find them, or the ‘coon had eaten their eggs or nestlings and then run the adult birds off. Looking around some more, I found a bald eagle nest on the property that had been hitherto unreported (my first “new” eagle nest!). This nest is located in an area with numerous cabbage palms (97% of Florida caracara nests are in cabbage palms), but the likelihood of the caracaras nesting so close to a pair of top carnivore raptors is probably slim. The irony is that this property has a lot of surface water, naturally and by wells, so its wetlands should be able to support a breeding pair and their young, maybe even two broodings. Egad!

Let’s hope that continued surveys of this property will reveal a third, successful nest for these hard working avians.