Wednesday, November 25, 2015

Butterfly News from SW FL

Some of you might enjoy seeing this butterfly newsletter from the Punta Gorda, Pt Charlotte, FL, area. It is packed with information and interesting trip reports.

Peace River Butterfly Society Newsletter -- November 2015


Saturday, November 21, 2015

Bird Brained ?‏

Snowy egret fishing at FL dock

Snowy egrets are known to be very versatile in their fishing styles which involve a variety of different ways to catch fish by wading.  Their most famous technique is the "snowy shuffle" in which their bright yellow feet are used to scare up small prey which are then grabbed by the beak.  But all of these procedures involve wading, and a limitation to water no deeper than their legs. This young genius snowy figured out that it can fish in deeper waters from our dock, but a "snowy stoop" is involved to reach the surface of the water from the dock.  As I watched, this bird was successful in catching several small minnows. So "bird brained" is not a bad thing from the perspective of this ability to solve a problem with a new idea.  Indeed the future of birds within a rapidly changing world so profoundly affected by humans could be largely dependent on such flexibility in behavior.

Bill Dunson
Englewood, FL

Nature walks by Bill Dunson in Nov/Dec 2015

Here are notices for four nature walks in SW FL sponsored by the Lemon Bay Conservancy which I am leading during Nov and Dec, 2015. No reservations required, meet in the parking lots,  and no fees except for parking at Stump Pass.  Please circulate this to your members.

Nov. 30:  Edible and medicinal plants at Wildflower Preserve. 3120 Gasparilla Pines Blvd. Englewood, FL. 9-11 am. A  short walk around the 80 acre restored golf course owned by the Lemon Bay Conservancy to examine the useful and toxic properties of plants and their animal herbivores and predators.

Dec. 4:  Hike the Duisberg Nature Trail and the beach at Middle Beach Park. 6725 Manasota Key Rd. Venice/Englewood, FL. 9-11 am.  A short hike up the nature trail and back on the beach to examine the natural history of a sub-tropical hammock, mangroves, and beach dunes.  

Dec. 11:  Hike about 1.5 miles round trip in Wildflower Preserve, 3120 Gasparilla Pines Blvd., Englewood, FL, to tidal Lemon Creek.  This is habitat for juvenile tarpon and we will discuss the ecology of such young fish living in hypoxic mangrove waters and efforts being made to study and restore/create habitat.  9-11:30 am. 

Dec. 18:  Hike about 2.5 miles round trip to Stump Pass within Stump Pass State Park (entry fee), Englewood, FL.  We will study the natural history of the beach, dune, back dune  and mangrove areas and discuss the current efforts to stabilize and re-nourish the eroding beach, and dredge the channel.  9-11:30 am. 

Dr Bill Dunson
276-233-6364 cell text

Friday, November 13, 2015

Nature is HOT in Florida Fall‏

Although I am generally anxious to leave our VA farm soon after the first frost, this year it has been unexpectedly warm in FL even into November.  This is a shock to humans unused to such hot and muggy weather, but it yields a bonus in that critters tend to be more active and plants flourish.

Lynx spider green female with egg mass 
This green lynx spider is guarding her eggs.  She does this apparently without eating and her shrunken abdomen illustrates her devotion to her progeny.  Such maternal behavior in higher life forms is considered commendable and even altruistic, but this illustrates how even primitive species are equally devoted to protection of their babies due to the evolutionary imperative to procreate their genes.    

Great pondhawk Bronco Rd FL 
I was happy to get this photo of a great pondhawk dragonfly, which I do not see very often; it is limited to S FL in the eastern US.  It has a huge thorax and a slender abdomen and is a rapacious predator on insects.  It is somewhat unusual in that the coloration of both sexes are similar and they strongly resemble the female (but not the bluish male) smaller eastern pondhawk.
There is so much we do not understand about the significance of such variation in color and pattern.

Hairstreak on mallow scrub
A very confusing group of butterflies is the hairstreaks.  On a hike in Charlotte Flatwoods Preserve we came across a number of the mallow scrub hairstreak which is restricted to S FL.  Not only are there other types of similar hairstreaks, but they also resemble the blues, both of which are tiny and require some study to identify.  Aside from the challenge of identification, I find these butterflies fascinating because of their unusual color and pattern.  The eye spot on the outer hindwing and the short "tails" appear to be an head mimic that is designed by evolution to divert the attack of  close-up predators such as jumping spiders away from the vulnerable head and body.  At a distance this butterfly is well camouflaged.

Clouded sulphur on salvia 
A butterfly that is certainly conspicuous is this clouded sulphur which is bright yellow, shown here drinking nectar on some red salvia flowers.  But its seems to limit predation by flying not only fast, but in an erratic pattern with short stops at flowers.  

Box turtle plastron
Box turtle carapace
The opposite extreme in animal locomotion is this FL box turtle which can only defend itself by closing up inside its shell when attacked.  The patterns on both the upper (carapace) and lower (plastron) shell are quite striking and illustrate how artistic natural coloration can be.  It might be that such beautiful patterns of the upper shell are actually a type of camouflage since they may disguise the shell by breaking up its outline in the dappled shade and sun of the forest floor.  

Coot among floating hearts
On a visit to Red Bug Preserve in Sarasota I found this coot feeding among the blooming floating hearts.  Not only was this a charming scene, it illustrates how coots and moorhens feed by picking up plant and animal material from the shallow surface waters.  The apparent decline of such birds that feed on shallow vegetation in lakes appears to be due to competition with the introduced African tilapia fish which is very common now in fresh water lakes.

Birds at FL dock
Wading birds are attracted to natural features of our yard which lies along the shores of Lemon Bay.  Thus in this photo you can see a little blue heron on the dock, and a single snowy egret and a group of white ibis feeding along the waters edge.  Such a mixed species flock seems to be of mutual benefit if contrasting feeding styles yield prey that may be less available when the species feed alone.  

Yellow throated warbler at FL yard water drip
Perching birds or passerines are primarily attracted in our barrier island yard to fresh water supplied by a drip; this yellow throated warbler likes to drink directly from the drip and then go down to the bowl and bathe.  

Soon enough we will be shivering from the periodic NE winds of cold fronts, but for now we enjoy the sultry southern breezes and the active behavior of animals uninhibited by cooler weather.

Bill Dunson 
Englewood, FL