NA­TURE'S NOTEBOOK

Fox Squir­rels of Florida

Times of the Islands - - Departments - BY WIL­LIAM R. C OX

Three species of fox squir­rels are na­tive to Florida: Sher­man’s ( Sci­u­rus niger sher­mani), south­ern ( S.n. niger) and Big Cy­press ( S.n. avi­cen­nia). Other Florida squir­rels in­clude the south­ern fly­ing squir­rel ( Glau­comys volans) and gray squir­rel ( S. car­o­li­nen­sis). Of the state’s three fox squir­rel species, the Sher­man’s and Big Cy­press can be found in South­west Florida, while the south­ern fox squir­rel lives in the Pan­han­dle. The Florida Fish and Wildlife Con­ser­va­tion Com­mis­sion (FFWCC) has des­ig­nated the Sher­man’s fox squir­rel as a “species of spe­cial con­cern” and the Big Cy­press fox squir­rel a “threat­ened” species.

The range of the Sher­man’s fox squir­rel stretches north of the Caloosa­hatchee River into Ge­or­gia. The Big Cy­press fox squir­rel ranges south of the Caloosa­hatchee River and west of the Ever­glades. Both squir­rels have a white muz­zle and white ears, black cheeks and crown and vari­able pelage col­oration. Sher­man’s fox squir­rels gen­er­ally ap­pear uni­formly tan, while a rare few are to­tally black. The Big Cy­press fox squir­rel is mostly or­ange-buff to rust with a dark back. The Sher­man’s fox squir­rel av­er­ages 25 inches in to­tal length (head, body and tail) and weighs 2.5 pounds, while the slightly smaller Big Cy­press fox squir­rel is 21 inches in to­tal length and weighs 2 pounds.

Habi­tat for the Sher­man’s fox squir­rel con­sists of open up­land pine/oak com­mu­ni­ties char­ac­ter­ized by a mix­ture of mast­pro­duc­ing trees, pri­mar­ily pine/oak as­sem­blages. This squir­rel also uses up­land hard­wood forests and bot­tom­land and cy­press domes if they are in­ter­spersed with or ad­ja­cent to pine/oak com­mu­ni­ties. In south-cen­tral Florida it uses im­proved sa­van­nalike pas­tures that are sim­i­lar to na­tive pine/oak habi­tats. It will also use golf cour­ses and sub­ur­ban parks. The Big Cy­press fox squir­rel lives mostly in slash pine flat­woods and cy­press forests that in­clude trop­i­cal hard­wood ham­mocks, man­grove for­est, live oak woods, parks and golf cour­ses. The cab­bage palm ( Sa­bal

pal­metto) is a com­mon com­po­nent of these habi­tats. The home range of the male fox squir­rel av­er­ages 100 acres in Florida, while home range for the fe­male av­er­ages 50 acres.

THE FLORIDA FISH AND WILDLIFE CON­SER­VA­TION COM­MIS­SION (FFWCC) HAS DES­IG­NATED THE SHER­MAN’S FOX SQUIR­REL AS A “SPECIES OF SPE­CIAL CON­CERN” AND THE BIG CY­PRESS FOX SQUIR­REL A “THREAT­ENED” SPECIES.

Male home ranges over­lap but their core ar­eas do not. The male does not de­fend his core ar­eas. Fe­male home ranges do not over­lap as ex­ten­sively as male home ranges, but the fe­male ag­gres­sively de­fends her core area from other fe­males. The fox squir­rel can travel up to 1.2 miles per day. The Sher­man’s fox squir­rel eats acorns, slash pine ( Pi­nus el­liot­tii) and lon­gleaf pine ( P. palus­tris) seeds. Other foods in­clude bulbs, veg­e­ta­tive buds, mush­rooms, in­sects, stami­nate pine cones, corn, peanuts and pecans. Acorns are col­lected in late Septem­ber; some will be cached. Pine cones are taken while green from May through Oc­to­ber.

The Big Cy­press fox squir­rel prefers slash pine seeds. It har­vests fe­male slash pine cones ( macrostro­bili) dur­ing the sum­mer and the male cones ( mi­crostro­bili) dur­ing the win­ter. Dur­ing the fall and win­ter the Big Cy­press fox squir­rel feeds on cy­press ( Tax­odium spp) cone seeds, as well as acorns, mush­rooms, queen palm ( Co­cos pamosa) fruit, cab­bage palm fruit, fig ( Fi­cus spp) fruit and bromeliad buds.

One of the most im­por­tant habi­tat com­po­nents for each of these fox squir­rels is food avail­abil­ity. Dur­ing years of lim­ited acorn pro­duc­tion sea­sonal habi­tat use pat­terns are greatly af­fected, and com­plete re­pro­duc­tive fail­ures will oc­cur.

Fox squir­rels are sex­u­ally ma­ture at nine months of age. In Florida the two sub­species have two pro­nounced breed­ing sea­sons. One ex­tends from late Novem­ber through Jan­uary, and the other from early May through Au­gust. Fe­males usu­ally pro­duce only one lit­ter per year. Mean lit­ter size is two, and the young re­main in the nest for ap­prox­i­mately 75 days. They are weaned when they are 3 months of age. It is not known how long Florida fox squir­rels live in the wild, but in cap­tiv­ity they have lived for 13 years.

In Florida the fox squir­rel rarely nests in true cav­i­ties but prefers plat­forms of twigs, leaves, Span­ish moss ( Til­land­sia us­neoides), pine nee­dles and other veg­e­ta­tive ma­te­rial. The nest of the Big Cy­press fox squir­rel also in­cludes strips of bark from cy­press and melaleuca ( Melaleuca quin­quen­ervia) trees. This sub­species places its nest in cy­press, melaleuca, slash pine and oaks. It con­structs as many as 30 nests per year and will use each nest for shelter once or up to and greater than 10 times. The Sher­man’s fox squir­rel places its nest high in oak trees and some­times in lon­gleaf pines.

The pop­u­la­tion of Florida fox squir­rels has been de­clin­ing over the past three decades from the con­ver­sion and loss of its pri­mary habi­tat of lon­gleaf pine and slash pine–dom­i­nated forests.

They’re van­ish­ing in alarm­ing num­bers. Yet lit­tle is be­ing done for mol­lusks—small in­ver­te­brates such as snails, clams, oys­ters and mus­sels. There are some 85,000 species, a few with a life­span of more than 100 years. Lost habi­tat and pol­lu­tion are push­ing some to­ward ex­tinc­tion, threats, sci­en­tists say, that af­fect us glob­ally.

Some in zo­ol­ogy are start­ing to pay closer at­ten­tion. About a dozen re­searchers and sci­en­tists lec­tured on Sanibel for the first “Mol­lusks in Peril” fo­rum in late May. The con­fer­ence was a “re­sound­ing suc­cess," says Dr. José H. Leal, sci­ence di­rec­tor and cu­ra­tor at the host Bai­ley-Matthews Na­tional Shell Mu­seum. “Through­out the meet­ing, the public in­ter­acted ex­ten­sively with the speak­ers, and new col­lab­o­ra­tions were forged.”

Ex­perts at the May 22-24 fo­rum pre­sented fact-find­ing sci­ence and our im­pact on mol­lusk sur­vival, says fresh­wa­ter re­searcher Dr. Arthur Bogan of North Carolina. Other speak­ers came from Mary­land, Wash­ing­ton, Hawaii and Aus­tralia, each with ex­per­tise in cli­ma­tol­ogy or marine life.

WORLD­WIDE, WE’RE IN A VERY SCARY PE­RIOD.” —DR. ARTHUR BOGAN, ON THE HEALTH OF MOL­LUSKS

“World­wide, we’re in a very scary pe­riod,” Bogan said fol­low­ing the three-day fo­rum. “The things we’re dump­ing in our waters, clear-cut­ting [forests] and global warm­ing—it’s fright­en­ing. Ev­ery­one loves a ver­te­brate; who could turn down a cud­dly panda? But 98 per­cent of [an­i­mal species] is be­ing over­looked. And the fo­rum pro­vided lots of good ques­tions, get­ting us talk­ing to one another, re­al­iz­ing we’re all fac­ing the same ques­tions and prob­lems.”

The Bai­ley-Matthews mu­seum is a lead­ing re­search/ex­hibit fa­cil­ity that at­tracts some 60,000 an­nual visi­tors. It seemed a per­fect fit for the mol­lusk fo­rum, says Dor­rie Hip­schman, the mu­seum’s ex­ec­u­tive di­rec­tor. “How can we pre­serve, pro­tect and ste­ward the frag­ile and en­dan­gered pop­u­la­tions of mol­lusks if peo­ple have never no­ticed that they are liv­ing? These are chal­lenges that the Na­tional Shell Mu­seum meets each day.”

Sher­man's fox squir­rel

Big Cy­press fox squir­rel

Re­searchers, sci­en­tists and staff at the Bai­ley-Matthews Na­tional Shell Mu­seum con­vened the first "Mol­lusks in Peril" fo­rum May 22-24 at the Sanibel-based mu­seum. The con­fer­ence was open to the public.

The Bai­ley-Matthews Na­tional Shell Mu­seum was a fit­ting back­drop for a se­ri­ous dis­cus­sion on the fu­ture of the im­per­iled mol­lusk around the world.

Newspapers in English

Newspapers from USA

© PressReader. All rights reserved.