Results

Two hundred and five (205) bird species plus mallard hybrids were recorded as confirmed, potentially breeding, or possibly breeding in Florida during the 2011-2016 BBA II surveys (Appendix 3: Table R1). Following the framework provided by Greenlaw et al. (2014) for native and exotic bird species in Florida, 185 species were considered established breeders in BBA II (Appendix 4: Table R3). Of these, 170 were endemic (Main List; ML) to Florida, 14 were established exotics (Main List Established Exotics; MLEE) that have self-sustaining populations (i.e., a population that has been maintained or increased for a period of 15 or more years), and 1 species (Whooping Crane) was reintroduced successfully. Twenty taxa were non-established exotics (Verifiable Non-established Exotics; VNEE) (Greenlaw et al. 2014; Appendix B, Part I). Mallard hybrids were also recorded in BBA II. One native North American species that was extirpated from Florida, Whooping Crane, was experimentally established between BBA I and BBA II, Atlasers recorded 186, 6, and 14 species as confirmed, probable, and possible breeders, respectively, in BBA II (Table R4). In comparison, 215 bird species were recorded during BBA I (FWC 2003; Appendix 3: Table R1), 170 species were established endemics (ML), and 13 were established exotics (MLEE) (Table R3). Purple Swamphen was recognized as an established exotic (MLEE) in the period between the two atlases. One species, the African Collared-Dove, was a verifiable, potential natural vagrant (VPNV) in BBA I, but it was not recorded in BBA II; 32 species were classified as verifiable, non-established exotics (VNEE; 12 in BBA I only, 3 in BBA II only, and 17 in both), and Crested Myna was classified as a non-verifiable, non-established exotic (NVNEE) (Table R3). Using the highest breeding category for each species recorded in all quads, 186 were confirmed, 14 were probable, and 6 were possible (Table R4).

One hundred ninety-eight bird species were recorded in both breeding bird atlas efforts in Florida (Table R1). Seventeen species (17) were recorded in BBA I but not BBA II. Of these species, only American Goldfinch and Worm-eating Warbler are native North American species, and the breeding ranges of both species just dip into northern Florida. Eight taxa were recorded in BBA II but not in BBA I:  Mallard hybrids, Purple Swamphen, Whooping Crane, Lilac-crowned Parrot, Green Parakeet, Tropical Kingbird, Bronzed Cowbird, and Scaly-breasted Munia (Table R1). Of these, only Bronzed Cowbird and Tropical Kingbird are apparently natural colonists, while Whooping Crane was a successful experimental re-introduction. The breeding status of 8 species failed to be confirmed in either BBA I or BBA II even though they were recorded in both:  Ring-necked Duck, Ring-necked Pheasant, Black Rail, American Bittern, Northern Harrier, Sharp-shinned Hawk, Yellow-naped Parrot, White-fronted Parrot, and Chipping Sparrow. Seven confirmed breeders in BBA I were recorded only as possible or probable in BBA II:  Hooded Merganser, Mangrove Cuckoo, Antillean Nighthawk, Belted Kingfisher, Eastern Phoebe, Shiny Cowbird, and Kentucky Warbler. The failure to confirm these species could be attributed to the instruction to atlas volunteers to “cover the country”. Thus, less time was spent confirming breeding in BBA II. The breeding status of 4 species – Egyptian Goose, Cliff Swallow, Bahama Mockingbird, and American Redstart – were all confirmed as breeders in BBA II after having been recorded as possible or confirmed in BBA I. Six species that were classified as unestablished exotics (VNEE) (Greenlaw et al. 2014) were recorded as confirmed breeders in both BBA I and BBA II:  Mute Swan, Indian Peafowl, Red-crowned Parrot, Blue-and-yellow Macaw, Mitred Parakeet, and Rose-ringed Parakeet. Populations of these species should be examined to determine if they have now become established breeders in the state.

QUADS VS. PRIORITY BLOCKS

Priority blocks are a subset of the quad data, thus, records for only priority blocks (Appendix 4: Table R2) resulted in fewer species — especially rare species — than quad level data. Only 187 (BBA I) and 184 species (BBA II) were recorded in the priority blocks versus 215 (BBA I) and 206 (BBA II) species in BBA I and II in quad-level data. One hundred and eighty-two species had data for both atlases using priority block data and 198 using quad data. Results from quads (i.e., the highest breeding category recorded within all 6 blocks in a quad) can be compared to the highest breeding category for priority blocks. The percentage of quads recorded for each species (Table R1 and R2) for quad and priority block data is highly correlated (R3₁₈₀ = 0.98; Figure R1). For example, Northern Cardinal (Figure R1; the uppermost righthand point) was recorded in 95% of the quads in BBA II and 81% of priority blocks. BBA II had procedure for assigning a block to be the priority block when block 6 could not be used (i.e., it was in water or inaccessible; see Methods), but which block was used in BBA I could not always be determined. Thus, some BBA I priority blocks were not comparable to priority blocks in BBA II. Given the greater number of species recorded in quads, the high correlation between the two data sets, and the presentation of quad-level data in BBA I, we used quad data for the BBA II analyses.