I have been working toward a routine of early morning jogging. A couple of weeks ago it was cool in the a.m., so out I went and jogged for 22 minutes straight. The next day I could only run for about 5 minutes because my hands were freezing (that’s my story and I’m sticking to it). Today I ran for 30 minutes. It is surprising to me that at my age and long hiatus at jogging, I can just go out and run that long without having to stop and rest a few times along the way. I am pleased.
I used to run almost every day for months at a stretch and then alternate with not running for an equivalent amount of time. Well ok, maybe the quit nickels were a little more than the run pennys. Each time I quit, I would have to retrain my body when I resumed. You know the drill: run for 5 minutes, walk for 5, run 5, walk 5… I used to have to do that several days in a row before I could run without walk-resting.
Then I learned I have a ticker problem; it is more like a zig-zag than a tick-tock. The ticker in my brain works fine, but the following cascade of 3 more tickers in my heart would tock out of order when I jogged or did other exertions. This causes the circulatory system to slow down and work less efficiently, effectively quashing endurance. My doctor put me on a derivative of digitalis, the deadly poison derived from the Old World foxglove plant, which straightened out the ticking. Mountain biking, hiking and caving are so much more enjoyable now, but I still hadn’t returned to jogging because of the boredom of it all and the uncertainty of how my (now) older heart would react.
Then a couple of days ago I learned that a long time friend had a heart attack. He awoke in the middle of the night with a pain under his arm and went quickly to a hospital where they installed a stent in one of three arteries that were clogged. He said his blood tests had always come back fine with cholesterol levels low. The doc said he might have died if he had gotten to the hospital much later. He has since learned there are better tests for circulatory problems than the standard tests that family doctors prescribe. Methinks I should review them, too.
Anyway, that was the motivation for running this morning. I remember how much I used to enjoy running, and now am reminded that it might be a good way to keep the arteries open. I find it ironic that a poisonous plant can give me so much life. To the survivors!
Dicromantispa interrupta
Mantisfly
Wednesday, October 28, 2009
Sunday, October 25, 2009
San Felasco and Gum Slough
The San Felasco Hammock Preserve State Park was the choice for Friday’s bike and hike. Bruce was recouperating from a bout with the flu, so we got a late start and only wandered about 9.5 miles that day. Using the GPS, existing bike and horse trails, and a variety of maps (topo, Google Earth, park trail maps), we were able to fill in some more of the puzzle (to me) that is the karst valley that ends in Sanchez Prairie. San Felasco is a special place that I never tire of exploring. It may be the closest thing around here to a large area of mature, natural vegetation spread across the transition zone between the impervious Northern Highlands and the karstic Newberry Plain. San Felasco also has small pockets of true “Old Growth Forest” if you know where to look. I know some of them, and continue to look for others.
San Felasco is pretty big for day trip explorations on foot, horseback or bicycle (no overnighters allowed - but maybe along the Florida Trail here?). The karst valley we are trying to tie down is smack in the middle between the north and south entrances to the park, there are no roads to it, the only trails to it are horse trails that bicyclists aren’t supposed to use, and the topography has a lot of ups and downs. In a nutshell, it is an aerobic little adventure to get there and another to come back, but they’re good ones. IMO, the trails are as challenging as the trails of the nationally renowned Santos Bike Trails Area, but are more scenic at San Felasco and are paths less traveled. The trails at Santos are on severely impacted property supporting raggedy early successional pine and hardwood forests plus old abandoned barge canal segments plus spoil piles and borrow pits and the like. It’s a great place to ride on red trails, though, and certainly more appropriate than San Felasco for ambitious, healthy mountain bikers who are not naturalists. Some of the trails at San Felasco are within early successional forests, too, but most of San Felasco’s trails run through mature hardwood forests or even older growth climax hardwood forests. Plus, the slope forests along the northern edge of Sanchez Prairie have that oak-beech look without the beech, but we can imagine…
On Saturday, Bruce, Brack and I did a bike and short hike trip at the Half Moon Wildlife Management Area in Sumter County, FL. The property encompasses 9,480 acres in the southeast corner of the confluence of the southern Withlacoochee River and Gum Slough. We got a late start on this 12.4-mile ride due to first attending an environmental expo in The Villages. We biked the main limerock road from the parking area at the northern end of CR 247 northward about 4 miles to Davies Road, intending to ultimately stand at the edge of Gum Slough Creek. There is a dirt road through the woods between and roughly paralleling the main road and the river-slough floodplain that would take us back to the parking area. We had intended to return via that route, but at that late hour it would have resulting in a death march along an unkempt road through hordes of ‘skeeters after dark. Nope. Didn’t.
Along Davies Road, we found a relatively easy route down into the Gum Slough floodplain where we stashed our bikes and hoofed it downhill. We almost made it to an eastern braid of the stream, but elected to keep our feet dry. This floodplain is not very level, but rather is crisscrossed with flood channels, natural streamside levees and natural rounded and elongated hillocks. Wet areas closer to the stream braids are dominated by mostly deciduous hardwoods like red maple and swamp tupelo, but we saw at least one pretty large sweetbay (Magnolia virginiana) almost 3 ft in diameter. The higher elevations supported a mature mid-successional mesic hardwood forest while intermediate elevations were dominated by a semi-evergreen hardwood forest dominated by live oak (Quercus virginiana). The latter habitat is also called “low hammock,” and is my favorite woods that we visited that day.
This low hammock is dominated by “too much” live oak, if there is such a thing. I say the former because it might compose over 50% of the overstory canopy, and I say the latter because live oak is a special tree. Driving down the highway you can see scads of live oaks out in Florida’s horse pastures. Their enormous 6-, 8- and 10-ft diameter trunks rise about a dozen feet off the ground and then multiple brontosaurian-necked limbs soar up and out and swoop down and spread out to form a hemisphere of photosynthesis a hundred feet in diameter and half that in height. Their limbs and trunks will be partially coated with resurrection fern and Spanish moss will cascade from their branches. If abandoned, that pasture will grow up into a forest dominated by those hemisphaerical, “open-grown” elders. You walk through that forest and think you are in an ancient copse because of the mightiness of their trunks, but in many cases they are less than a hundred years old, so don’t be fooled! The next step in the successional trend of the forest is exemplified by the low hammock habitat along Gum Slough, which you can see behind the below-pictured live oak:
Look at the form of that tree. Obviously, it is not a hemisphaerical, open-grown tree. That trunk rises almost straight up for about 45 feet before it first branches, and the trunk at that height is about 3 ft in diameter. This is a forest-grown tree, one that got its start in a small clearing that was created by a tree dying there long ago, allowing sunlight to reach the mature second-growth forest floor to energize the live oak of today. Notice the trunk is covered near the ground by bryophytes (true mosses). If you could see the limbwork high over Bruce’s and Brack’s heads, you could observe that resurrection fern and Spanish moss have been joined by several more epiphytes like ball moss, Bartram’s moss and several other Tillandsias, plus two orchids, the green-fly orchid (Epidendrum conopseum) and Tampa butterfly orchid (Encyclia tampensis). In truly old-growth live oak forests, there are more species of trees in the overstory and live oaks have a much higher density of epiphytes, at least in low hammocks.
The next time I visit Half Moon, and I certainly intend to, I will take the woods road and go looking for karst outcrops along the river and slough floodplain and its edge. Let me know if you want to go.
San Felasco is pretty big for day trip explorations on foot, horseback or bicycle (no overnighters allowed - but maybe along the Florida Trail here?). The karst valley we are trying to tie down is smack in the middle between the north and south entrances to the park, there are no roads to it, the only trails to it are horse trails that bicyclists aren’t supposed to use, and the topography has a lot of ups and downs. In a nutshell, it is an aerobic little adventure to get there and another to come back, but they’re good ones. IMO, the trails are as challenging as the trails of the nationally renowned Santos Bike Trails Area, but are more scenic at San Felasco and are paths less traveled. The trails at Santos are on severely impacted property supporting raggedy early successional pine and hardwood forests plus old abandoned barge canal segments plus spoil piles and borrow pits and the like. It’s a great place to ride on red trails, though, and certainly more appropriate than San Felasco for ambitious, healthy mountain bikers who are not naturalists. Some of the trails at San Felasco are within early successional forests, too, but most of San Felasco’s trails run through mature hardwood forests or even older growth climax hardwood forests. Plus, the slope forests along the northern edge of Sanchez Prairie have that oak-beech look without the beech, but we can imagine…
On Saturday, Bruce, Brack and I did a bike and short hike trip at the Half Moon Wildlife Management Area in Sumter County, FL. The property encompasses 9,480 acres in the southeast corner of the confluence of the southern Withlacoochee River and Gum Slough. We got a late start on this 12.4-mile ride due to first attending an environmental expo in The Villages. We biked the main limerock road from the parking area at the northern end of CR 247 northward about 4 miles to Davies Road, intending to ultimately stand at the edge of Gum Slough Creek. There is a dirt road through the woods between and roughly paralleling the main road and the river-slough floodplain that would take us back to the parking area. We had intended to return via that route, but at that late hour it would have resulting in a death march along an unkempt road through hordes of ‘skeeters after dark. Nope. Didn’t.
Along Davies Road, we found a relatively easy route down into the Gum Slough floodplain where we stashed our bikes and hoofed it downhill. We almost made it to an eastern braid of the stream, but elected to keep our feet dry. This floodplain is not very level, but rather is crisscrossed with flood channels, natural streamside levees and natural rounded and elongated hillocks. Wet areas closer to the stream braids are dominated by mostly deciduous hardwoods like red maple and swamp tupelo, but we saw at least one pretty large sweetbay (Magnolia virginiana) almost 3 ft in diameter. The higher elevations supported a mature mid-successional mesic hardwood forest while intermediate elevations were dominated by a semi-evergreen hardwood forest dominated by live oak (Quercus virginiana). The latter habitat is also called “low hammock,” and is my favorite woods that we visited that day.
This low hammock is dominated by “too much” live oak, if there is such a thing. I say the former because it might compose over 50% of the overstory canopy, and I say the latter because live oak is a special tree. Driving down the highway you can see scads of live oaks out in Florida’s horse pastures. Their enormous 6-, 8- and 10-ft diameter trunks rise about a dozen feet off the ground and then multiple brontosaurian-necked limbs soar up and out and swoop down and spread out to form a hemisphere of photosynthesis a hundred feet in diameter and half that in height. Their limbs and trunks will be partially coated with resurrection fern and Spanish moss will cascade from their branches. If abandoned, that pasture will grow up into a forest dominated by those hemisphaerical, “open-grown” elders. You walk through that forest and think you are in an ancient copse because of the mightiness of their trunks, but in many cases they are less than a hundred years old, so don’t be fooled! The next step in the successional trend of the forest is exemplified by the low hammock habitat along Gum Slough, which you can see behind the below-pictured live oak:
Look at the form of that tree. Obviously, it is not a hemisphaerical, open-grown tree. That trunk rises almost straight up for about 45 feet before it first branches, and the trunk at that height is about 3 ft in diameter. This is a forest-grown tree, one that got its start in a small clearing that was created by a tree dying there long ago, allowing sunlight to reach the mature second-growth forest floor to energize the live oak of today. Notice the trunk is covered near the ground by bryophytes (true mosses). If you could see the limbwork high over Bruce’s and Brack’s heads, you could observe that resurrection fern and Spanish moss have been joined by several more epiphytes like ball moss, Bartram’s moss and several other Tillandsias, plus two orchids, the green-fly orchid (Epidendrum conopseum) and Tampa butterfly orchid (Encyclia tampensis). In truly old-growth live oak forests, there are more species of trees in the overstory and live oaks have a much higher density of epiphytes, at least in low hammocks.
The next time I visit Half Moon, and I certainly intend to, I will take the woods road and go looking for karst outcrops along the river and slough floodplain and its edge. Let me know if you want to go.
Monday, October 19, 2009
San Felasco State Park Bike and Hike
I did a 6-hour,12-mile bike and hike around the NE portion of San Felasco State Park Sunday yesterday, picked up some interesting GPS points. It was a good, cool day in a primo Florida mixed hardwood forest and I really enjoyed it. While sitting on the ground eating my lunch, a 4-point white-tailed deer run almost straight up to me until it saw me about 30ft away and stopped. Wide-eyed, he didn’t know at first what to do, as I remained still, but then he bounded away. The find of the day was a terrific rat snake, as best as I can figure an intergrade between the gray rat snake (Elaphe obsoleta spiloides) and the yellow rat snake (Elaphe obsolete quadrivittata). It was fully 7 feet long and 1.75 inches in diameter, perhaps the largest rat snake I have ever seen in the Florida wilds. It was stretched across the park bike trail. I stopped to photograph it and move it out of the way of further bike traffic. As I bent down to pick it up, the snake retracted into a coil beside the trail and then raised itself up into this imperious image:
Another interesting find was a nest or bedding platform, or something like that, put together by some kind of wildlife in a marsh. It was composed of the large grass (Poaceae) species dominating the marsh and did not look like it had been deposited there by running water (the marsh is in a karst-origin expansion of an otherwise well-defined stream floodplain):
Another interesting find was a nest or bedding platform, or something like that, put together by some kind of wildlife in a marsh. It was composed of the large grass (Poaceae) species dominating the marsh and did not look like it had been deposited there by running water (the marsh is in a karst-origin expansion of an otherwise well-defined stream floodplain):
Tuesday, October 6, 2009
Frog and turtle note
This morning’s short walk around the yard produced a couple of nature observations worthy of historical documentation. First out of the box was a turtle. No, not a box turtle, but a striped mud turtle, Kinosternon bauri, looking muddy and knackered, possibly blind in the left eye:
Judging by all the dried dirt that covered her, I think she was headed back to the water after laying a load of eggs. She was so tired that she protested not at all when I stopped to photograph and handle her. That was a bit surprising, as a little mud turtle can be feisty. Looking closer, it was evident that the dirt on her body was dry despite the long soaking rain yesterday evening and last night. All the bare dirt in the yard is a sandy clayey organic mud (former lake bottom) that is very hard when not moist from rain, so her nest must be in a dry, sheltered place. I’m guessing it may have been under my RV or that of the neighbor.
I do not normally handle turtles out of respect for their personal space, and because they can claw blood and bite the crap outta ya, but she was headed for a fall – literally – her direction would have taken her over a 5 ft vertical bulkhead to crash down on a creosoted timber. That would have been bad for any small turtle at any time, but in her condition the fall could have stunned her long enough for predators or even ants to take advantage of. I released the turtle directly into the water instead.
Then I moseyed over to a blooming Aloe vera and spotted three green treefrogs, Hyla cinerea, sitting motionless among the flowers. Here is one of them, along with scads of some kind of tiny, unknown insect, perhaps an aphid:
This aloe flowerhead is out in the open where it will soon be bright, hot and dry, so I imagine the treefrogs will head for darker, moister places shortly. By day, lynx spiders hang out on flowers waiting for pollinators to make themselves available to prey on, and by night treefrogs occupy the ambush niche. We must plant more flowers.
Judging by all the dried dirt that covered her, I think she was headed back to the water after laying a load of eggs. She was so tired that she protested not at all when I stopped to photograph and handle her. That was a bit surprising, as a little mud turtle can be feisty. Looking closer, it was evident that the dirt on her body was dry despite the long soaking rain yesterday evening and last night. All the bare dirt in the yard is a sandy clayey organic mud (former lake bottom) that is very hard when not moist from rain, so her nest must be in a dry, sheltered place. I’m guessing it may have been under my RV or that of the neighbor.
I do not normally handle turtles out of respect for their personal space, and because they can claw blood and bite the crap outta ya, but she was headed for a fall – literally – her direction would have taken her over a 5 ft vertical bulkhead to crash down on a creosoted timber. That would have been bad for any small turtle at any time, but in her condition the fall could have stunned her long enough for predators or even ants to take advantage of. I released the turtle directly into the water instead.
Then I moseyed over to a blooming Aloe vera and spotted three green treefrogs, Hyla cinerea, sitting motionless among the flowers. Here is one of them, along with scads of some kind of tiny, unknown insect, perhaps an aphid:
This aloe flowerhead is out in the open where it will soon be bright, hot and dry, so I imagine the treefrogs will head for darker, moister places shortly. By day, lynx spiders hang out on flowers waiting for pollinators to make themselves available to prey on, and by night treefrogs occupy the ambush niche. We must plant more flowers.
Sunday, October 4, 2009
Sunday bicycling around the north side of Orange Lake
Tuesday I wrote about tievine, a wild morning glory growing around the perimeter of Orange Lake. That morning tievine bloomed en masse just off the causeway extending out into the lake marsh. It had saggitate leaves and its blossoms were 3 inches in diameter, and I mentioned that the leaves varied in form to include a heart shape, too. This morning a few yards away from Tuesday’s mass bloom there was another mass bloom of tievine, but this time the leaves were heart shaped and the blooms were very small, about an inch across. When researching tievine Tuesday I learned that a single gene is responsible for smallness in the morning glory family, so evidently the same gene that makes this patch of tievine have small flowers is the same gene responsible for small flowers in cypress-vine and quamoclit:
It is interesting that the small- and large-flowered forms bloom separately but only a few days apart. Is this speciation in action or just individual variation on nearby plants? Parsimoniously, I bet the latter.
Not having had any real exercise for the last week, I girded my loins for a long road and trail bike ride and pedaled off through McIntosh, Boardman and Edmiston, headed north to the River Styx and then a little further to Grove Park Wildlife Management Area (WMA) on the NE side of Orange Lake. Along the way a grass spider (Agelenopsis sp.) with its stand-out funnel web caught my eye:
Possibly, there was another, smaller spider that came out when I was photographing and then ran back in before I could get a look at it. Moving on, I was apprehensive as I approached the WMA parking area, but was relieved to see no parked vehicles. That meant hunters had knocked off for the morning and would not return until late afternoon. In I went, wearing a dull yellow shirt. It looked like much of the upland pine flatwoods habitat had burned a year or so ago, reducing here and eliminating there the shady planted pine canopy long enough ago that native wildflowers were bustin’ out all over. I have mentioned before my admiration for pine flatoods wildflower richness, and this example of it did not let me down. I do not know this wildflower, but it was common in the flatwoods and was a clear favorite of the butterflies:
Whatever it is, other pollinators love it too. Here is a close-up of the flower head:
Here’s another pic of the flower head, but this one has a cool shot of a Gulf fritillary, or passion butterfly (Agraulis vanillae), feeding with proboscis extended:
But the standout of the flatwoods today was blazing star, or dense gayfeather (Liatris spicata), because it was truly abundant everywhere in the uplands and along the graded dirt roads:
Its showier sister species, pinkscale gayfeather (Liatris elegans), was occasionally seen, and a third sister, deer tongue or vanilla leaf Liatris odoratissima), was locally abundant. Its vanilla fragrance can often be smelled as you pedal by.
There were many more wildflower species blooming, of course, like a white-flowered rose gentian (Sabatia [difformis]), meadow beauty (Rhexia sp.), and a white-flowered “yellow-eyed grass” (Xyris sp.). The trip was a little more than 22 miles long, mileage-wise being mostly on paved roads, but considering time and exhaustion factors it was the WMA that did it – and my knees are killing me! You will push your pedals nearly every step of the way for the mildly soft sand and moderately high bahia grass on the dirt roads. Oh, and stay on the dirt roads, as the woods are furrowed, stumpy and wracked. I got out just as three hunters were coming in for the late afternoon hunt, though – perfect timing!
It is interesting that the small- and large-flowered forms bloom separately but only a few days apart. Is this speciation in action or just individual variation on nearby plants? Parsimoniously, I bet the latter.
Not having had any real exercise for the last week, I girded my loins for a long road and trail bike ride and pedaled off through McIntosh, Boardman and Edmiston, headed north to the River Styx and then a little further to Grove Park Wildlife Management Area (WMA) on the NE side of Orange Lake. Along the way a grass spider (Agelenopsis sp.) with its stand-out funnel web caught my eye:
Possibly, there was another, smaller spider that came out when I was photographing and then ran back in before I could get a look at it. Moving on, I was apprehensive as I approached the WMA parking area, but was relieved to see no parked vehicles. That meant hunters had knocked off for the morning and would not return until late afternoon. In I went, wearing a dull yellow shirt. It looked like much of the upland pine flatwoods habitat had burned a year or so ago, reducing here and eliminating there the shady planted pine canopy long enough ago that native wildflowers were bustin’ out all over. I have mentioned before my admiration for pine flatoods wildflower richness, and this example of it did not let me down. I do not know this wildflower, but it was common in the flatwoods and was a clear favorite of the butterflies:
Whatever it is, other pollinators love it too. Here is a close-up of the flower head:
Here’s another pic of the flower head, but this one has a cool shot of a Gulf fritillary, or passion butterfly (Agraulis vanillae), feeding with proboscis extended:
But the standout of the flatwoods today was blazing star, or dense gayfeather (Liatris spicata), because it was truly abundant everywhere in the uplands and along the graded dirt roads:
Its showier sister species, pinkscale gayfeather (Liatris elegans), was occasionally seen, and a third sister, deer tongue or vanilla leaf Liatris odoratissima), was locally abundant. Its vanilla fragrance can often be smelled as you pedal by.
There were many more wildflower species blooming, of course, like a white-flowered rose gentian (Sabatia [difformis]), meadow beauty (Rhexia sp.), and a white-flowered “yellow-eyed grass” (Xyris sp.). The trip was a little more than 22 miles long, mileage-wise being mostly on paved roads, but considering time and exhaustion factors it was the WMA that did it – and my knees are killing me! You will push your pedals nearly every step of the way for the mildly soft sand and moderately high bahia grass on the dirt roads. Oh, and stay on the dirt roads, as the woods are furrowed, stumpy and wracked. I got out just as three hunters were coming in for the late afternoon hunt, though – perfect timing!
Thursday, October 1, 2009
Orange Lake Fish Kill
Lynn and I rendezvoused at Heagy Burry Park on the south side of Orange Lake for a late afternoon canoe paddle. We headed out straight into the wind for a couple of miles NNE along the open path through dense submerged macrophytes to the edge of the big lake’s open water. She had told me about gobs o' ‘gators on the south side of the lake up in the weed cuts and airboat trails, and I had never canoed around in that part of the lake.
As we pulled away from the boat ramp we noticed a few dozen dead, rotting fish floating in the weeds just off the boat path. Most were a foot or more in length and torpedo-shaped, so I expected them to be bowfin (Amia calva) and/or gar (Lepisosteus spp.) because local anglers often catch and then deliberately kill them, and throw them back in the water. Why do they kill them? When I was a boy, my older fishing fellows insisted that we kill rough fish because that would make room for more eatin’ fish in the lake for us to catch. Sheesh! Anyway, when we pulled over to examine them I was shocked to see they were chain pickerel (Esox niger) instead! We saw one that was easily 18 inches in length, but it sank out of sight when we tried to maneuver it for photography. This other one was only about 14 inches long:
A very few of the dead fish were sunfishes (Centrarchidae), I saw a largemouth bass (Micropterus salmoides) and an unidentified bream (Lepomis sp.), but there were no dead gar or bowfin. The great majority of the dead fish were chain pickerel, a delicious fish that anglers readily keep. Pickerel are among the most finicky of our Peninsular Florida fishes, needing cleaner water and more dissolved oxygen than sunfishes. Could the killer instead be nocturnal dissolved oxygen deficits? Orange Lake and the other large lakes in the Orange Creek Basin are hypereutrophic and have frequent blooms of blue-green algae (Cyanobacteria), dominated by Cylindrospermopsis raciborskii (http://tinyurl.com/ybby3x5). The new satellite images of Orange Lake on Google Earth clearly show a massive algae bloom in January 2008, possibly from “cylindro:”
How about that? A huge algae bloom in mid-winter! Do you think the bloom might extend all the way to Heagy Burry boat ramp by late September? (Or was its photosignature simply not picked up by the next image?) As I have noted before, the lake’s enormous submerged macrophyte biomass also depresses nocturnal oxygen levels. Between macrophytes in the shallows and cylindro in deep waters, there could be a huge deficit of dissolved oxygen just before dawn on a hot summer day like the one we had a few days ago. That could kill a sensitive taxon like Esox, which could be likened to a canary taken into a mine to warn miners of bad air.
Or was the kill caused by a toxin? Cylindro produces cylindrospermopsin, which in sufficient quantities results in closure of public lake beaches in Indiana (http://tinyurl.com/y99uof8). The Indiana group also pointed out that cylindro is positively related to elevated dissolved phosphorus levels, which Orange Lake certainly has. This toxin has been implicated in deaths of mice, cattle, shellfish, fish, horses, sheep, dogs, birds, bats and muskrats (http://tinyurl.com/y85hftl). In humans it has caused skin rash, fever, hay fever-like symptoms, hepatoenteritis and toxic hepatitis (http://tinyurl.com/y85hftl).
Or was the fish kill a result of too much toxin and too little oxygen working in synergy?
Moving right along…
We ran across a couple of patches of yellow water lily, Nymphaea mexicana. I had never seen it before, and I’ve been on a LOT of Florida’s freshwaters taking inventory of plants and such, and was therefore certain it was an exotic. But no, the Center for Aquatic and Invasive Weeds (http://aquat1.ifas.ufl.edu/node/289) lists it as a native of Florida. How could I have missed this plant after all these years of wandering around Florida’s aquatic ecosystems? Egad! Having fewer petals, it is not as showy as its sister species, white water lily (N. odorata), but it does also have a very pleasant fragrance:
At that we turned around and headed slowly for the ramp with the wind at our backs, reaching shore as the sun was setting and a three-quarter moon rising higher. A group of black vultures was coming back to the ramp too, for the snag roosts there. It was a good ending to a fine early fall day.
As we pulled away from the boat ramp we noticed a few dozen dead, rotting fish floating in the weeds just off the boat path. Most were a foot or more in length and torpedo-shaped, so I expected them to be bowfin (Amia calva) and/or gar (Lepisosteus spp.) because local anglers often catch and then deliberately kill them, and throw them back in the water. Why do they kill them? When I was a boy, my older fishing fellows insisted that we kill rough fish because that would make room for more eatin’ fish in the lake for us to catch. Sheesh! Anyway, when we pulled over to examine them I was shocked to see they were chain pickerel (Esox niger) instead! We saw one that was easily 18 inches in length, but it sank out of sight when we tried to maneuver it for photography. This other one was only about 14 inches long:
A very few of the dead fish were sunfishes (Centrarchidae), I saw a largemouth bass (Micropterus salmoides) and an unidentified bream (Lepomis sp.), but there were no dead gar or bowfin. The great majority of the dead fish were chain pickerel, a delicious fish that anglers readily keep. Pickerel are among the most finicky of our Peninsular Florida fishes, needing cleaner water and more dissolved oxygen than sunfishes. Could the killer instead be nocturnal dissolved oxygen deficits? Orange Lake and the other large lakes in the Orange Creek Basin are hypereutrophic and have frequent blooms of blue-green algae (Cyanobacteria), dominated by Cylindrospermopsis raciborskii (http://tinyurl.com/ybby3x5). The new satellite images of Orange Lake on Google Earth clearly show a massive algae bloom in January 2008, possibly from “cylindro:”
How about that? A huge algae bloom in mid-winter! Do you think the bloom might extend all the way to Heagy Burry boat ramp by late September? (Or was its photosignature simply not picked up by the next image?) As I have noted before, the lake’s enormous submerged macrophyte biomass also depresses nocturnal oxygen levels. Between macrophytes in the shallows and cylindro in deep waters, there could be a huge deficit of dissolved oxygen just before dawn on a hot summer day like the one we had a few days ago. That could kill a sensitive taxon like Esox, which could be likened to a canary taken into a mine to warn miners of bad air.
Or was the kill caused by a toxin? Cylindro produces cylindrospermopsin, which in sufficient quantities results in closure of public lake beaches in Indiana (http://tinyurl.com/y99uof8). The Indiana group also pointed out that cylindro is positively related to elevated dissolved phosphorus levels, which Orange Lake certainly has. This toxin has been implicated in deaths of mice, cattle, shellfish, fish, horses, sheep, dogs, birds, bats and muskrats (http://tinyurl.com/y85hftl). In humans it has caused skin rash, fever, hay fever-like symptoms, hepatoenteritis and toxic hepatitis (http://tinyurl.com/y85hftl).
Or was the fish kill a result of too much toxin and too little oxygen working in synergy?
Moving right along…
We ran across a couple of patches of yellow water lily, Nymphaea mexicana. I had never seen it before, and I’ve been on a LOT of Florida’s freshwaters taking inventory of plants and such, and was therefore certain it was an exotic. But no, the Center for Aquatic and Invasive Weeds (http://aquat1.ifas.ufl.edu/node/289) lists it as a native of Florida. How could I have missed this plant after all these years of wandering around Florida’s aquatic ecosystems? Egad! Having fewer petals, it is not as showy as its sister species, white water lily (N. odorata), but it does also have a very pleasant fragrance:
At that we turned around and headed slowly for the ramp with the wind at our backs, reaching shore as the sun was setting and a three-quarter moon rising higher. A group of black vultures was coming back to the ramp too, for the snag roosts there. It was a good ending to a fine early fall day.
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