Browsing by Subject "Computer software"

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    Open Access
    Gauging the threat: the first population estimate for white sharks in South Africa using photo identification and automated software
    (Public Library of Science, 2013) Towner, Alison V; Wcisel, Michelle A; Reisinger, Ryan R; Edwards, David; Jewell, Oliver J D
    South Africa is reputed to host the world’s largest remaining population of white sharks, yet no studies have accurately determined a population estimate based on mark-recapture of live individuals. We used dorsal fin photographs (fin IDs) to identify white sharks in Gansbaai, South Africa, from January 2007 - December 2011. We used the computer programme DARWIN to catalogue and match fin IDs of individuals; this is the first study to successfully use the software for white shark identification. The programme performed well despite a number of individual fins showing drastic changes in dorsal fin shape over time. Of 1682 fin IDs used, 532 unique individuals were identified. We estimated population size using the open-population POPAN parameterisation in Program MARK, which estimated the superpopulation size at 908 (95% confidence interval 808-1008). This estimated population size is considerably larger than those described at other aggregation areas of the species and is comparable to a previous South African population estimate conducted 16 years prior. Our assessment suggests the species has not made a marked recovery since being nationally protected in 1991. As such, additional international protection may prove vital for the long-term conservation of this threatened species.
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    Open Access
    Ten simple rules for organizing a virtual conference - anywhere
    (Public Library of Science, 2010) Gichora, Nelson N; Fatumo, Segun A; Ngara, Mtakai V; Chelbat, Noura; Ramdayal, Kavisha; Opap, Kenneth B; Siwo, Geoffrey H; Adebiyi, Marion O; Gonnouni, Amina El; Zofou, Denis