A rare Santa Catalina Island fox, Urocyon littoralis catalinae, at Catalina Island Conservancy.
Photograph by Joël Sartore, National Geographic Photo Ark
A Florida scrub jay, Aphelocoma coerulescens oocleptica, at Tracy Aviary.
Photograph by Joël Sartore, National Geographic Photo Ark
A critically endangered flattened musk turtle, Sternotherus depressus.
Photograph by Joël Sartore, National Geographic Photo Ark
Narrow-headed garter snake, Thamnophis rufipunctatus, at the Phoenix Zoo.
Photograph by Joël Sartore, National Geographic Photo Ark
A spotted seal, Phoca largha, at the Alaska SeaLife Centre.
Photograph by Joël Sartore, National Geographic Photo Ark
A Kentucky Arrow Darter, Etheostoma spilotum, at Conservation Fisheries.
Photograph by Joël Sartore, National Geographic Photo Ark
A federally threatened Southeastern beach mouse, Peromyscus polionotus niveiventris. There are only a few thousand of this species left.
Photograph by Joël Sartore, National Geographic Photo Ark
A vulnerable, federally threatened male Steller's eider, Polysticta stelleri, at the Alaska SeaLife Centre.
Photograph by Joël Sartore, National Geographic Photo Ark
An American crocodile, Crocodilus acutus, at the Omaha Zoo.
Photograph by Joël Sartore, National Geographic Photo Ark
Oregon spotted frog, Rana pretiosa, in Deschutes County, OR.
Photograph by Joël Sartore, National Geographic Photo Ark
A wood stork, Mycteria Americana, at the Sedgwick County Zoo.
Photograph by Joël Sartore, National Geographic Photo Ark
A Yellow-blotched map turtle, Graptemys flavimaculata. This species is listed as vulnerable.
Photograph by Joël Sartore, National Geographic Photo Ark
A Stock Island tree snail, Orthalicus reses reses, a federally-endangered species.
Photograph by Joël Sartore, National Geographic Photo Ark
A federally threatened New Mexican ridge-nosed rattlesnake, Crotalus willardi obscurus.
Photograph by Joël Sartore, National Geographic Photo Ark
An endangered juvenile Yosemite toad, Bufo or Anaxyrus canorus.
Photograph by Joël Sartore, National Geographic Photo Ark
Manchado, a near threatened Mexican spotted owl, Strix occidentalis, at The Wildlife Center in Espanola, NM.
Photograph by Joël Sartore, National Geographic Photo Ark
A crayfish, Cambarus callainus, wild caught near Dry Fork, West Virginia.
Photograph by Joël Sartore, National Geographic Photo Ark
Red knot, Calidris canutus, a candidate species for listing due to a rapid decline in population.
Photograph by Joël Sartore, National Geographic Photo Ark
A frosted flatwoods salamander, Ambystoma cingulatum, at the Atlanta Botanical Garden. This species is listed as vulnerable.
Photograph by Joël Sartore, National Geographic Photo Ark
A spectacled Eider, Somateria fischeri.
Photograph by Joël Sartore, National Geographic Photo Ark
An eastern indigo snake, Drymarchon corais couperi.
Photograph by Joël Sartore, National Geographic Photo Ark
A salado salamander, Eurycea chisholmensis, at the Dallas Zoo.
Photograph by Joël Sartore, National Geographic Photo Ark
Spring pygmy sunfish, Elassoma alabamae, taken at Conservation Fisheries in Knoxville, TN.
Photograph by Joël Sartore, National Geographic Photo Ark
A federally threatened Gopher tortoise, Gopherus polyphemus.
Photograph by Joël Sartore, National Geographic Photo Ark
Snail darter, Percina tanasi, at Conservation Fisheries in Knoxville, TN.
Photograph by Joël Sartore, National Geographic Photo Ark
An endangered Piping plover, Charadrius melodus.
Photograph by Joël Sartore, National Geographic Photo Ark
A federally threatened ringed map turtle, Graptemys oculifera.
Photograph by Joël Sartore, National Geographic Photo Ark
