Thursday, February 26, 2015

Waiting Impatiently for "Spring" in SW Florida‏

Male brown anole dewlap
A recent family visitor asked me when Spring starts in SW FL.  A cogent question which I answered by saying it depends on how you define "Spring," by planetary motion (March 20) or by ecology, and then which natural signs you choose.  Certainly based on ecology there is no single start to spring but many different ones.  My primary definition of Spring based on amphibian breeding was partially fulfilled on Feb. 12 when I heard the first chorus frog calling. 

Zebra butterfly sunning in FL yard
In our yard at present we have mainly zebra heliconian butterflies which are long-lived and resistant to cold.  Their caterpillars feed on corky stem passionvine which is abundant in our yard.  The butterflies can fly on days when other lepidopterans are immobile and I noticed that this individual was sunning itself in a spot protected from the wing by holding its wings open perpendicular to the sun.  This type of behavioral thermoregulation allows for activity on sunny days with cool air temperatures.   

Cuban tree frog in palm leaf at Wildflower
I found some Cuban tree frogs hunkered down inside a leaf of cabbage palm and they may also benefit from some solar heating on cool days.  But they are mainly waiting for the summer rains which are still far away before they can breed.  Night time dews provide the moisture they need in the interim.  Brown anoles are abundant and active even in February and are masters of finding a sunny spot to bask.  This large male was doing pushups to assert his dominance and even extended his bright dewlap which likely deters rival males and attracts females.

Banded snowy plover
In the avian world migrations will soon begin for most species.  I found a banded snowy plover on Palm Island that will likely be returning to the FL Panhandle to breed.  It was banded in St Joseph State Park in July and the pattern of colorful "bling" on its legs identify it positively. Many snowy plovers migrate only a relatively short distance compared to the Arctic breeders such as sanderlings, red knots and turnstones that are now still common on our beaches.  

Whimbrel and reddish egret at the Spit
Just beyond the plover I sighted a spectacular Caribbean resident the reddish egret, and by coincidence there was a rare whimbrel nearby.  The whimbrel will soon be heading to the arctic.  I noticed a Bonaparte's gull which has been present in abnormally large numbers in FL this winter.  It lacks the dark hood which will soon develop during the breeding season.  Such periodic occurrences of northern birds may indicate unusual circumstances in their normal wintering grounds.  Several years ago razorbill auks migrated south to FL and then disappeared.  These atypical movements may be the result of climate change or just be caused by natural fluctuations in food supply.    

Bald eagle over Stump Pass
Overhead I saw an adult bald eagle which was soaring on thermal air currents. They are winter breeders in FL so their presence tells us nothing about the beginning of Spring.  An adult yellow crowned night heron in our yard had a distinctive reddish eye; changes in leg color and plumes accompany  the onset of breeding season.  But the surest sign of the continuing winter season is the presence of large numbers of yellow-rumped warblers which are winter residents only.  They will soon be winging their way to their far northern breeding territories.

Adult yellow crowned night heron
So here in late February I conclude that true "Spring" is yet to come, although there are early signs that it is near.

Bill Dunson
Englewood, FL and Galax, VA

Yellow-rumped warblers

Saturday, February 21, 2015

Saving the Monarch Butterfly‏

From: Ray Smith (smith460@hotmail.com)
Sent:Sat 2/21/15 12:16 PM

Folks,
I wrote to Bill Dunson for his take on planting milkweed here on the Island/SW Fla to possibly help the Monarch butterflies.  His quick response was as follows:
 
“It is a complicated and contentious issue but my answer is no to planting exotic milkweeds which are likely to cause disease problems in  monarchs and cause them to remain in FL longer than they should.  Bill”
 
He then followed up with the attached (and very recent) article on this subject, (CLICK HERE TO READ ARTICLE) starting on page 5.  It basically details what Bill said above; quoting:
 
“But a new paper shows that well-meaning gardeners might actually be endangering the butterflies’ iconic migration to Mexico. That’s because people have been planting the wrong species of milkweed, thereby increasing the odds of monarchs becoming infected with a crippling parasite.”

It goes on to specify the “tropical” variety as the “bad” milkweed, whereas there is a specific “native” variety that is considered good (to plant) for these beautiful creatures.  And suggesting that any “tropical” be cut back routinely to prevent Monarch attraction and possible parasitic infection.  The article is pretty definitive.
 
So, do we want to publish this on our PIE website?  Do the Islanderscapers want to tackle this subject/inform our residents?  Or just ignore as “just not important?”  I trust not the last thought.

Ray

Sent: Monday, February 16, 2015 8:21 PM
Subject: Fwd: PRBS Meeting & NL
 
 
See this newsletter for an article about the monarch milkweed issue
 
Few things are simple in life and this is one of the complicated ones
 
Bill

Friday, February 20, 2015

Winter Flowers Dazzle the Eye in SW Florida‏

Myakka State Forest Gordon Smith Trail
You do not normally expect to see native flowers blooming in winter, but this can happen in Florida after fires release nutrients and expose the soil to light. Although winter is not the natural time for most fires, which would have normally occurred after summer lightning, a prescribed burn about two months ago in Myakka State Forest led to an explosion of flower production. Members of the mangrove chapter  of the Florida Native Plant Society (http://mangrove.fnpschapters.org/ ) walked the Gordon Smith Trail on Feb. 12 and enjoyed seeing a remarkable profusion of winter blooms.  The habitat there is a combination of mesic and hydric pine flatwoods with occasional shallow, gently sloping natural wetlands.
Sundew at Myakka State Forest

Since the soils in this area are predominantly sterile, acidic quart sands eroded from the Alabama and Georgia mountains, fires mobilize scarce nutrients that were held in the existing plants and litter, stimulating other plants to grow and bloom. It reminds me of the famous early spring flush of wildflowers in northern woodlands  which seem timed to catch sunlight before the tree leaves have fully emerged.  

Bladderwort Utricularia cornuta
The scarcity of nutrients also favors plants that are carnivorous and can derive essential metabolites from animal flesh.  Three species of such remarkable carnivores (remember the movie "Little Shop of Horrors" ) in bloom were the yellow butterwort, the horned bladderwort and the sundew.  

Butterwort plutea at Myakka State Forest
Each of these animal-eaters has a different mechanism to catch their prey.  The butterwort has sticky leaves, the bladderwort has tiny traps on its roots, and the sundew has sticky droplets on the ends of its leaves, all of which ensnare small creatures.  Thus nitrogen, phosphorus and minerals can  be obtained which otherwise are not only scarce in the soil but subject to severe competition among plants.   



Sabatia
A very striking flower we saw was the Sabatia or marsh pink.  Its five pink petals surround a yellow center bordered by red.  This central design is thought to serve as a "bulls eye" to guide insects to the nectar reward and thus to cross pollinate the flowers.  It might surprise you to know that the marsh pink is related to gentians.

An unusual flower we found was the pine hyacinth or leather flower, a type of pinewoods Clematis in the buttercup family.  It is only found in Florida and has a very strange seed pod structure consisting of long hairy filaments which bear no resemblance to the flower.  Its bluish color suggests that it is particularly attractive to bumblebees as pollinators. (picture at right with photo of pine hyacinth seed below)
Close to the pine hyacinth we found a number  of procession flowers with a very different pinkish color and shape.  These are a type of milkwort which have several close relatives in wet pine flatwoods such as bachelor's buttons, drumheads and candy root.   These thrive in sandy soils and some species have bright orange flowers.

Sneezeweed, Helenium
A large and spectacular yellow flower in the edge of a wetland was the sneezeweed, Helenium.  It is another of those "dyc" plants, the darn yellow composites that can be difficult to identify.  The composites or asters are an amazing family of plants whose "flower" is actually made up of hundreds of individual flowers that comprise both the apparent petals (ray flowers) and the central area of disc flowers.  The ray flowers do not usually reproduce but contribute to the fitness of their relatives in the disc which produce large numbers of seeds.  This "socialistic" strategy of flower structure is extremely successful and highly evolved in comparison with simple primitive flowers such as the magnolias.

So a walk in the woods and fields this time of year need not be without the chance to see wonderful flowers.  Look for places where fire has occurred and follow the changes in vegetation over time and you will be richly rewarded by a profusion of interesting flowers.

Bill Dunson
Englewood, FL and Galax, VA

A Mid-Winter Nature Ramble in SW Florida‏

 Can you see the yellow crowned night heron in the top picture?  Look again at the bottom close-up!


Despite the regular procession of cool fronts we continue to enjoy seeing a lot of wildlife and some flowers in SW Florida in early February.  But you may notice that I feature more birds than insects since the cool weather does reduce the sightings of butterflies and dragonflies and other chitinous creatures.  The first willow blooms of the season have been with us for several weeks and always seem early when encountered.  But I need to keep better track of the "phenology" or seasonal timing of blooms.  Are they early this year or not?  It is difficult to remember for sure so some records would be handy.  Put that on the New Years Resolution list !

Sand pine cones_Prairie Shell
We are all familiar with the common slash pines and the less common longleaf pines, but how many of you have seen the sand pine?  It has shorter needles in groups of two.  I have seen it in an area near the Englewood water plant and most recently at the Prairie Shell Preserve.  It is famous for its strange method of reproduction in which the cones remain closed until a fire burns them and releases the seeds. This process is termed serotiny.   Often the tree is consumed in the fire also, so the process resembles that of the mythical Phoenix.  

Long tailed skipper lacking tails in FL yard
An interesting phenomenon is occurring with a butterfly which has no certain answer yet.  Long tailed skippers are being sighted which lack their beautiful tails and the question is why.  I show one example here from my yard.  Are the tails being bitten off by predators?  Are they actually designed to attract predators and thus save the head from attack?  Or is there a genetic variant of the species which simply lacks tails?  Another of nature's many mysteries which invites further observation.

Yellow-throated warbler in FL yard
One of my favorite warblers is the yellow-throated which visits our yard water baths occasionally and feeds in our numerous cabbage palms.  Its coloration is interesting since the male and female are nearly identical and the basic black and white pattern is broken only by a bright yellow throat.  Since sexual recognition cannot be involved with this coloration which does not change during  the breeding season, what is its primary purpose?  Perhaps it is designed to assist with species recognition among the sometimes confusing group of wood warblers?  

Yellow-crowned night heron juvenile
One of our yard birds which undergoes distinct changes in plumage with maturation is the yellow-crowned night heron.  We enjoy seeing these almost daily in our large mangrove trees as they forage for crabs or rest quietly.  The immature herons  are streaked and virtually invisible when motionless in the mangroves.  Only their red iris betrays their presence.  The heavy all dark bill is their hallmark and distinguishes them from the immature black-crowned night heron which has a more slender and partly light colored bill.  The adults have a bold pattern on the head, again likely related to species recognition, but from a distance this also blends in the mangrove background surprisingly well.  

Roseate spoonbill at Lemon Lake
One bird that definitely does not blend into the background is the roseate spoonbill.  It is a treat to see them and as the waters of Lemon Lake fall, spoonbills and other wading birds are attracted to the increasing prey density in this estuarine area. Here again we have a bright coloration which is shared by both male and female.  Perhaps female birds of any species may assume a dull coloration only when they need to be camouflaged when they incubate the eggs?  The spatulate bill of the spoonbill is even more remarkable than its color and seems to be designed by evolution to screen out suitably sized prey of any type from murky waters.  It is one more example of how different bird species divide the prey base among themselves by variation in the method of prey capture.  

Bald eagle juvenile at Lemon Lake
While watching for spoonbills at Lemon Lake a young bald eagle flew overhead and spread fear among the ducks and coots.  It also attracted the attention of an angry osprey which dive-bombed it in an effort to scare it away.  This juvenile or basic one plumage eagle is almost a year old and is changing its feathers over a four year period before achieving the iconic adult coloration.  Why does this huge raptor undergo such a long period of maturation and why does its plumage change so slowly?   Certainly once attaining adult colors the eagle will enter a world of intense competition for nesting sites and food; a gradual process of entering this adult world may reduce intraspecific competition.  So in Florida where golden eagles are extremely rare, sighting of a brownish eagle provides a puzzle for the observer to judge the age of the bird.

Willow in bloom at Amberjack
I suddenly realized that our six months stay in Florida is half over, and the cool winters will soon enough be a memory.   Excitement is beginning to build for the arrival of  the northern spring which is presaged already by a flush of flowers in the pine flatwoods.

Bill Dunson
Englewood, Fl and Galax, VA

Tuesday, February 3, 2015

Wildflower walk Feb 7‏



There is an unusual opportunity this Saturday Feb. 7 to go on a wildflower walk at the Myakka State Forest.  As part of the North Port Ecofest (see attached article) there will be a bus tour to the forest to walk (about 1.2 miles) the Gordon Smith Trail and afterwards go to Warm Mineral Springs for a presentation by Steve Koski on the two local sink hole springs which are so interesting.

Jim Brower and I with help from Stu Lewis on birds will lead the walk at Myakka State Forest.  The Gordon Smith Trail was burned about two months ago and there has been an incredible outburst of flowers including some that are rarely seen.  This flush of flowers after a burn is comparable to the early spring flowers in NE forests but is not often seen and appreciated in Florida.  For example how many of you have seen the carnivorous yellow butterwort in bloom?

The article below explains how you will need to sign up starting at 11:45 am Feb. 7 at the Friends of Wildlife table at the Ecofest (at N Port City Hall, 4970 City Hall Blvd just off Sumter Blvd), with a departure of the bus at 12:30 pm.  The bus is limited to 50 and there is a donation of $5 each.

Bill Dunson


Amazing Fallen Leaf Colors‏


Sea grapes which grow just behind the beach dunes have leaves that are huge and beautiful even in their normal green growth period, but when they drop off the trees in mid-winter they can be very colorful.  When I held this one up to the sun it showed an amazing contrast between the reddish leaf tissue and the green veins which circulate the fluids from the tree to the leaf.  Who says we don't have fall/winter leaf colors in Florida?

Bill Dunson

Pretty in Pink‏

Spoonbill at Lemon Lake

Water levels are dropping in Lemon Lake (Amberjack Preserve at the end of Gasparilla Pines Blvd) and the spoonbills are back.  Shallower waters concentrate prey and make wading possible for these spectacular filter feeders.  Two boardwalks allow for easy viewing when the birds are nearby so take this chance to enjoy these and other beautiful water birds such as green winged teal which are unusually common this year.

Bill Dunson