Charles Knapp

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Energy-minimizing active contour models or snakes can be used in many applications such as edge detection, motion tracking, image matching, computer vision, and three-dimensional (3-D) reconstruction. We present a novel snake that is superior both in accuracy and convergence speed over previous snake algorithms. High performance is achieved by using spline(More)
Deliberately feeding wildlife is an increasingly popular tourism-related activity despite a limited understanding of long-term impacts on the species being fed. As a result, tourist behaviours that may have adverse impacts on imperiled species have often been encouraged without the necessary evaluation or oversight. Here, we report the responses of Northern(More)
Ample evidence confirms that large invasive mammalian competitors and predators can devastate endangered insular iguana populations. However, the impact of invasive rodents, particularly rats (Rattus rattus), has remained elusive. Tail autotomy occurs frequently in lizards, often as an antipredator tactic, but sometimes from intraspecific aggression. Tail(More)
Ecological data, the primary source of information on patterns and rates of migration, can be integrated with genetic data to more accurately describe the realized connectivity between geographically isolated demes. In this paper we implement this approach and discuss its implications for managing populations of the endangered Andros Island Rock Iguana,(More)
We conducted a temperature-dependent reproductive study on Yellow Stingrays (Urobatis jamaicensis) at the John G. Shedd Aquarium, Chicago, Illinois. A group of eight and six female rays were mated in 22°C ("cold") and 27°C ("warm") water, respectively, over a two-year period. Mating behavior, gestation length, pup yields, body condition indices, and(More)
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