This Is AuburnElectronic Theses and Dissertations

Habitat use, survival, and reproductive success of female Florida mottled ducks (Anas fulvigula fulvigula) using the Everglades Agricultural Area and urban habitats of south-eastern Florida

Date

2013-10-11

Author

Varner, Dana

Type of Degree

dissertation

Department

Forestry and Wildlife Sciences

Abstract

The most recent Conservation Plan for the Florida Mottled Duck identified several areas where knowledge of the species is incomplete. This study was initiated to provide critical information needed for the development of a more comprehensive management plan for Florida mottled ducks (Anas fulvigula fulvigula). I radio-tagged 246 adult female mottled ducks in southeast Florida in order to collect survival, nesting, and habitat use data. I found that median home range sizes of rural females were more than 65 times greater than those of urban females. There was little movement (6%) between urban and rural areas. Urban females mostly used low and high intensity urban habitats. Rural ducks preferred freshwater marshes throughout the year, but selection of other habitat types varied seasonally. Artificial impoundments and reservoirs were particularly important during the post-breeding (1 Aug – 18 Nov) and hunting (19 Nov – 31 Jan) seasons. I found that annual survival was lower for ducks that did not use urban areas (47%) compared to those that did (74%). Daily survival rates were lowest during the breeding season (1 Mar–31 Jul). Females that used Everglades-type habitat during the breeding season had higher seasonal survival rates (78 – 85%) than those that did not (37 – 47%). Differences in hunting season survival for ducks that used non-hunted rural areas (88%) when compared to those that used open (87%) or quota-hunting systems (85%) were minimal. I located and monitored 56 nests in southeast Florida (2009-2011) and also used data from 21 nests found in the Upper St. Johns River Basin (1999–2002) iii during a prior study. Daily nest survival rates did not vary within or among years and were unaffected by density and height of vegetation at the nest and human disturbance parameters. Breeding propensity ranged from 25–56%. Breeding propensities were less than those of other duck species, but our nest success estimate of 28% was greater than most estimates for ducks and is not likely to limit population growth of Florida mottled ducks. My results indicate that female Florida mottled ducks do well in urbanized areas but may benefit from conservation and management of rural habitats, especially during the breeding season.