Animal Diversity Web

Ge­o­graphic Range

Florida scrub jays, Aph­e­lo­coma coerulescens, occur from the Florida pan­han­dle through cen­tral Florida. Florida scrub jays pre­vi­ously oc­cu­pied most of the coun­ties of penin­su­lar Florida, they are cur­rently found from Fla­gler, Mar­ion, and Cit­rus coun­ties in the north to Col­lier, Glades, and Palm Beach coun­ties in the south. (Sny­der, 1992)

• Biogeographic Regions
• nearctic
  • native

Habi­tat

Aph­e­lo­coma coerulescens is a habi­tat spe­cial­ist, liv­ing mainly in scrub wood­lands of penin­su­lar Florida. These birds pre­fer thick­ets of sand pine and scrub oak, re­cently burned sites, and shore-dune thick­ets, all habi­tats found on the sandy soils of this area. Aph­e­lo­coma coerulescens is found in scrub habi­tats along coasts, rivers, and on some high in­land ridges. They will not gen­er­ally nest in heav­ily forested areas. Dom­i­nant tree species in Florida scrub jay habi­tat are sand live oak (Quer­cus vir­gini­ana), Chap­man oak (Quer­cus chap­manii), myr­tle oak (Quer­cus myr­ti­fo­lia), and scrub oak (Quer­cus in­opina). Florida scrub jays may also be found in sub­ur­ban areas. ("South Florida multi-species re­cov­ery plan", 1999; Sny­der, 1992; Sul­li­van, 1994)

• Habitat Regions
• temperate
• terrestrial

• Terrestrial Biomes
• scrub forest

• Other Habitat Features
• suburban
• riparian

• Range elevation

  0 to 200 m

  0.00 to 656.17 ft

Phys­i­cal De­scrip­tion

Aph­e­lo­coma coerulescens is usu­ally be­tween 25 and 30 cm long and weighs about 77 grams. The plumage of adult males and fe­males looks alike, but males are slightly larger than fe­males. The head, nape, wings, and tail are pale blue. The back and belly are pale gray. The throat and chest are white and bor­dered by a blue gray bib. Ju­ve­niles dif­fer in ap­pear­ance from adults in that they have dull or dark brown up­per­parts. Florida scrub jays look sim­i­lar to other jays (Cyanocitta), but do not have a crest, white-tipped wings or tail feath­ers, or black bar­ring. Molt­ing oc­curs be­tween June and No­vem­ber, and is at its high­est be­tween July and Sep­tem­ber. Dur­ing late sum­mer and early fall ju­ve­niles can­not be dis­tin­guished from adults. ("Na­tional Audubon So­ci­ety", 2002; "South Florida multi-species re­cov­ery plan", 1999; For­bush, 1925; Sul­li­van, 1994)

• Other Physical Features
• endothermic
• homoiothermic
• bilateral symmetry

• Sexual Dimorphism
• male larger

• Average mass

  77 g

  2.71 oz

• Average mass

  78.7 g

  2.77 oz

  AnAge

• Range length

  25 to 30 cm

  9.84 to 11.81 in

• Average wingspan

  43 cm

  16.93 in

Re­pro­duc­tion

Florida scrub jays mate for life. This species uses a tech­nique called co­op­er­a­tive breed­ing, where ex­tended fam­i­lies live to­gether but have only one breed­ing pair. Courtship of a breed­ing pair is drawn out, with males using vo­cal­iza­tions and pos­tur­ing to at­tract fe­males. Av­er­age nest­ing groups con­sist of three birds, but can range from two to eight. Helper birds are usu­ally the young of the orig­i­nal breed­ing pair. Cop­u­la­tion is dis­creet and not vis­i­ble to other jays. Helper jays help the breed­ing pair by de­fend­ing the ter­ri­tory and pro­vid­ing food for young. Helper birds are re­pro­duc­tively ca­pa­ble, and ev­i­dence sug­gests that they delay breed­ing be­cause they are un­likely to be suc­cess­ful in re­pro­duc­ing. When helpers do go on to be­come breed­ers in a new nest, males gen­er­ally in­herit their natal ter­ri­tory when the breed­ing male dies. Fe­males em­i­grate from their natal area. If the mate of a breed­ing adult dies, that adult may take on helper roles and re­lin­quish their role as a breeder. ("South Florida multi-species re­cov­ery plan", 1999; Schoech, 1998)

• Mating System
• monogamous
• cooperative breeder

Nest­ing oc­curs from early March to late June. Florida scrub jays breed for the first time be­tween the ages of 1 and 7 years, with most in­di­vid­u­als breed­ing for the first time be­tween 2 and 4 years of age. The eggs of are pea green to pale glau­cous green and spot­ted with ir­reg­u­larly shaped mark­ings. Helper male birds have lower testos­terone lev­els than breed­ing males. ("South Florida multi-species re­cov­ery plan", 1999; Schoech, 1998; Sny­der, 1992)

• Key Reproductive Features
• iteroparous
• seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• fertilization
• oviparous

• Breeding interval

  Florida scrub jays produce one clutch per season.

• Breeding season

  Breeding occurs from early March through late June.

• Range eggs per season

  1 to 5

• Average eggs per season

  3-4

• Average eggs per season

  4

  AnAge

• Average time to hatching

  17-18 days

• Average time to hatching

  17 days

  AnAge

• Range fledging age

  16 to 21 days

• Average time to independence

  10 weeks

• Average age at sexual or reproductive maturity (female)

  1 years

• Average age at sexual or reproductive maturity (female)
  Sex: female

  365 days

  AnAge

• Average age at sexual or reproductive maturity (male)

  1 years

• Average age at sexual or reproductive maturity (male)
  Sex: male

  365 days

  AnAge

Fledg­lings de­pend on adults for food for about 10 weeks. Only the breed­ing pair builds the nest; which is about 18 to 20 cm in outer di­am­e­ter, and 9 to 10 cm inner di­am­e­ter. Nests are usu­ally 1 to 2 me­ters from the ground. Only the breed­ing fe­male in­cu­bates the eggs. Feed­ing of fledg­lings is done by both the breed­ing pair and helper birds. Helper birds do not in­cu­bate eggs or brood nestlings. Florida scrub jays use a look­out tech­nique to watch for preda­tors where one bird is cho­sen as the look­out and watches for on­com­ing at­tacks from a high po­si­tion. Breed­ers and helpers will help chase away egg preda­tors, which can be other species or other Florida scrub jays. ("South Florida multi-species re­cov­ery plan", 1999; Garvin, et al., 2002; Schoech, 1998)

• Parental Investment
• altricial
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • male
    • female
• pre-weaning/fledging
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• pre-independence
  • protecting
    • male
    • female
• post-independence association with parents
• inherits maternal/paternal territory

Lifes­pan/Longevity

Av­er­age lifes­pan is 4.5 years, but Florida scrub jays are known to live for up to 11 years in the wild. (Sny­der, 1992)

• Range lifespan
  Status: wild

  15.8 (high) years

• Average lifespan
  Status: wild

  4.5 years

• Average lifespan
  Status: wild

  179 months

  Bird Banding Laboratory

Be­hav­ior

Aph­e­lo­coma coerulescens is both so­cial and ter­ri­to­r­ial. Fam­ily mem­bers co­op­er­ate in breed­ing, hunt­ing, and de­fense. They are strongly ter­ri­to­r­ial and use a look­out sys­tem to keep other mem­bers of the nest safe from harm. One bird perches on a high point and looks for preda­tors. When one is spot­ted, the look­out gives a spe­cific call to alert fam­ily mem­bers to take cover. Fe­males use a dis­tinc­tive hic­cup call when in­ter­act­ing with other in­di­vid­u­als. Nest­ing groups of A. coerulescens work to­gether in for­ag­ing and ter­ri­tory de­fense. There is a dom­i­nance scheme in the fam­ily struc­ture, breed­ing males are most dom­i­nant, fol­lowed by helper males, breed­ing fe­male, and helper fe­males. The breed­ing ter­ri­tory is in­her­ited by the helper male when the breed­ing male dies or is un­able to con­tinue to breed. The helper fe­males branch out from the nest­ing area and as­sume breed­ing roles in other ter­ri­to­ries when they leave the nest. Birds from one ter­ri­tory have been known to work to­gether to prey on the eggs from an­other brood. This has been known to occur when only the breed­ing fe­male is pro­tect­ing the eggs and a group of in­vad­ing in­di­vid­u­als come near the nest. The breed­ing fe­male head bobs and hic­cups at the in­trud­ers and chases after them when they get too close to the nest. While she is chas­ing one in­truder, an­other may enter the nest and steal an egg. These birds are also known to prac­tice co­op­er­a­tive hunt­ing of other species. In­di­vid­u­als may mob a large ver­te­brate in de­fense or hunt­ing, and also have been ob­served to hunt snakes in pairs. Florida scrub jays are di­ur­nal. ("South Florida multi-species re­cov­ery plan", 1999; Bow­man, 2003; Garvin, et al., 2002)

• Key Behaviors
• arboreal
• flies
• diurnal
• motile
• sedentary
• territorial
• social
• dominance hierarchies

• Range territory size

  50,000 (low) m^2

• Average territory size

  90,000-100,000 m^2

Home Range

Florida scrub jay ter­ri­to­ries av­er­age 9 to 10 hectares, but are known to be as small as 5 hectares. The main lim­it­ing fac­tor for ter­ri­tory size is habi­tat avail­abil­ity. ("South Florida multi-species re­cov­ery plan", 1999)

Com­mu­ni­ca­tion and Per­cep­tion

Florida scrub jays com­mu­ni­cate using vi­sual cues such as head bob­bing; a move­ment used dur­ing ter­ri­to­r­ial en­coun­ters. The com­plex­ity of their co­op­er­a­tion in de­fense, breed­ing, and hunt­ing also sug­gests that in­tra-nest com­mu­ni­ca­tion is im­por­tant. They use vo­cal­iza­tions to ex­change in­for­ma­tion and warn preda­tors, such as the hic­cup sound pro­duced by fe­male birds. An­other ex­am­ple of this is the warn­ing calls that these birds use to alert each other to the pres­ence of preda­tors. ("South Florida multi-species re­cov­ery plan", 1999; Garvin, et al., 2002)

• Communication Channels
• visual
• acoustic

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

These birds gen­er­ally for­age near the ground. They search for food by hop­ping along the ground. Acorns are the most im­por­tant part of the diet, which they bury and cache for later use. Other nuts and fruits are also eaten. Florida scrub jays also eat in­sects, such as grasshop­pers (Or­thoptera) and but­ter­flies and moths (Lep­i­doptera), bird eggs, and small ver­te­brates such as frogs, snakes, lizards, and mice. Some of these are Hyla cinerea, H. squirella, Ano­lis car­o­li­ne­nis, A. sagrei, Cne­mi­dopho­rus sex­lin­ea­tus, Col­u­ber con­stric­tor, Tan­tilla re­licta re­licta, Opheodrys aes­tivus, Mus mus­cu­lus, Per­omyscus gossyp­i­nus, P. po­liono­tus, and Podomys flori­danus. Foods of­fered by hu­mans are also eaten as a sup­ple­ment. ("South Florida multi-species re­cov­ery plan", 1999)

• Primary Diet
• omnivore

• Animal Foods
• mammals
• amphibians
• reptiles
• eggs
• insects
• terrestrial non-insect arthropods

• Plant Foods
• seeds, grains, and nuts
• fruit

• Foraging Behavior
• stores or caches food

Pre­da­tion

Florida scrub jays de­fend them­selves against preda­tors by using look­outs to give warn­ings to other birds. They are so­cial, alert, and ag­gres­sive and will ac­tively mob preda­tors. Scrub jays may be preyed on by preda­tory birds, such as hawks and fal­cons, or by do­mes­tic cats and bob­cats. ("South Florida multi-species re­cov­ery plan", 1999)

• Known Predators

  • Cooper's hawk (Accipiter cooperii)
  • sharp-shinned hawks (Accipiter striatus)
  • merlins (Falco columbarius)
  • northern harriers (Circus cyaneus)
  • peregrine falcons (Falco peregrinus)
  • domestic cats (Felis silvestris)
  • bobcats (Lynx rufus)

Ecosys­tem Roles

Florida scrub jays play a role in main­tain­ing pop­u­la­tion lev­els of in­sects and small ver­te­brates on which they feed. They also act as seed dis­persers of scrub oaks (Quer­cus species) by caching acorns. This species is also known to eat ticks from the backs of large mam­mals such as white-tailed deer (Odocoileus vir­gini­anus). ("South Florida multi-species re­cov­ery plan", 1999)

• Ecosystem Impact
• disperses seeds

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

These birds are well-loved by bird watch­ers. They have beau­ti­ful bright blue col­ors and are ac­tive and vocal. They are im­por­tant sub­jects for re­search on the evo­lu­tion of co­op­er­a­tion. ("South Florida multi-species re­cov­ery plan", 1999)

• Positive Impacts
• ecotourism
• research and education

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

There are no known ad­verse ef­fects of A. coerulescens on hu­mans

Con­ser­va­tion Sta­tus

Over­all num­bers of A. coerulescens are de­clin­ing mainly due to habi­tat loss, even though most of its re­main­ing habi­tat is pub­lic land. In an ef­fort to stop this habi­tat de­struc­tion, land is being set aside to be left in a nat­ural state where fires clear the area and cre­ate a scrub habi­tat. Some land is being al­lo­cated to be burned at reg­u­lar in­ter­vals, and only por­tions will be burned at a time. Also, to avoid satel­lite sys­tems, where groups of birds are ge­o­graph­i­cally iso­lated from the larger group, cor­ri­dor con­nec­tions are being made in Florida Scrub-Jay habi­tat. ("South Florida multi-species re­cov­ery plan", 1999)

• IUCN Red List

  Vulnerable
  More information

• IUCN Red List

  Vulnerable
  More information

• US Migratory Bird Act

  Protected

• US Federal List

  Threatened

Other Com­ments

Aph­e­lo­coma coerulescens once in­cluded scrub jays in Cal­i­for­nia and Mex­ico as well, with the dif­fer­ent pop­u­la­tions iden­ti­fied as sub­species. Re­cently, this species has been re­vised so that A. coerulescens only in­cludes Florida scrub jay pop­u­la­tions. Other scrub jays are now A. cal­i­for­nica, west­ern scrub jays, and A. ul­tra­ma­rina, Mex­i­can jays or gray-breasted jays. Is­land scrub jays, A. in­su­laris, occur on Santa Cruz Is­land, off the coast of Cal­i­for­nia. Tax­o­nomic re­vi­sions were based on ge­netic and be­hav­ioral ev­i­dence. An ex­am­ple of be­hav­ioral ev­i­dence is that only Florida scrub jays use a co­op­er­a­tive breed­ing strat­egy. ("TAX­O­NOMIC CHANGES AND THE BBS DATA­BASE", 2001; Banks, 1983)

Con­trib­u­tors

Tanya Dewey (ed­i­tor), An­i­mal Di­ver­sity Web.

Eric Wohlford (au­thor), Kala­ma­zoo Col­lege, Ann Fraser (ed­i­tor, in­struc­tor), Kala­ma­zoo Col­lege.

Ref­er­ences

1999. South Florida multi-species re­cov­ery plan. At­lanta, Geor­gia: U.S. Fish and Wildlife Ser­vice. Ac­cessed No­vem­ber 19, 2005 at http://​www.​fws.​gov/​southeast/​vbpdfs/​species/​birds/​fsja.​pdf.

2002. "Na­tional Audubon So­ci­ety" (On-line). Florida Scrub-Jay. Ac­cessed No­vem­ber 19, 2005 at http://​audubon2.​org/​webapp/​watchlist/​viewSpecies.​jsp?​id=84.

2001. "TAX­O­NOMIC CHANGES AND THE BBS DATA­BASE" (On-line). U.S. Ge­o­log­i­cal Sur­vey. Ac­cessed No­vem­ber 21, 2005 at http://​72.​14.​203.​104/​search?​q=cache:​Dl0t3iDCbGkJ:​www.​pwrc.​usgs.​gov/​bbs/​bbsnews/​AOUsplt1.​htm+florida+scrub-jay+taxonomy+change&​hl=en.

Banks, R. 1983. "Ob­so­lete Eng­lish Names of North Amer­i­can Birds and their Mod­ern Equiv­a­lents" (On-line). Ac­cessed No­vem­ber 22, 2005 at http://​www.​pwrc.​usgs.​gov/​infobase/​obsnames/​obsname2.​pdf.

Bow­man, R. 2003. Ap­par­ent Co­op­er­a­tive Hunt­ing in Florida Scrub-Jays. The Wil­son Bul­letin, 115/2: 197-199.

For­bush, E. 1925. A Nat­ural His­tory of Amer­i­can Birds of East­ern and Cen­tral North Amer­ica. New York: Bramhall House.

Garvin, J., J. Reynolds, S. Schoech. 2002. Con­spe­cific Egg Pre­da­tion by Florida Scrub-Jays. The Wil­son Bul­letin, 114/1: 136-139.

Schoech, S. 1998. Phys­i­ol­ogy of Help­ing in Florida Scrub-Jays. Amer­i­can Sci­en­tist, 86: 70-77.

Sny­der, S. 1992. "Fire Ef­fects In­for­ma­tion Sys­tem" (On-line). Aph­e­lo­coma coerullescens. Ac­cessed No­vem­ber 19, 2005 at http://​www.​fs.​fed.​us/​database/​feis/​wildlife/​bird/​apco/​all.​html.

Sul­li­van, J. 1994. "Quer­cus in­cana" (On-line). Fire Ef­fects In­for­ma­tion Sys­tem. Ac­cessed No­vem­ber 21, 2005 at http://​72.​14.​203.​104/​search?​q=cache:​eIG5AokS-n8J:​www.​fs.​fed.​us/​database/​feis/​plants/​tree/​queinc/​all.​html+florida+oak+scrub+elevation&​hl=en.