Michelle Jewell

North Carolina State University | NCSU · Applied Ecology

There may be no such thing as a free meal, but many species have evolved mechanisms for other species to consume the literal fruits of their labors. In the present article, inspired by a chef's recognition that such species are “nature's chefs,” we consider food-making species from the plant, animal, and fungal kingdoms, which produce food or mimic...

Introduction: Ineffective health communication can drive health disparities and limit the effectiveness of interventions to reduce them. Stock photo libraries are a critical tool for developers of patient education, health education, and intervention materials. It is not clear how well stock photo libraries represent communities bearing disproport...

White sharks (Carcharodon carcharias) are described as generalist predators, with a demonstrated ontogenetic dietary shift which occurs between subadult and adult life stages. Trophic ecology studies on white shark have been focused mainly on large and mature individuals, necessitating studies of young white shark trophic ecology to better understa...

This study provides the first insight into the trophic ecology of young white sharks using stable isotopes analysis (SIA) in muscle tissues to characterize prey contributions and ontogenetic changes in habitat use.

White sharks, Carcharodon carcharias, are often described as elusive, with little information available due to the logistical difficulties of studying large marine predators that make long-distance migrations across ocean basins. Increased understanding of aggregation patterns, combined with recent advances in technology have, however, facilitated...

Original source: www.sharkwatchsa.com/projects/great-white-habitat

Refugia play an important role in shaping predator/prey interactions; however, few studies have investigated predator–prey relationships between large marine vertebrates, mainly due to the logistical challenges of studying marine species. The predictable interactions between Cape fur seals and white sharks in South Africa at two neighbouring seal c...

Manual acoustic telemetry was used to describe core habitat use of white sharks in the complex marine landscape of the Dyer Island and Geyser Rock system near Gansbaai, South Africa. We compared home range estimates and swimming pattern analyses to those established at Mossel Bay, another white shark aggregation area roughly 300 km to the east. Tra...

Originally published on http://www.sharkwatchsa.com/projects/agents-of-seal/

Predators and the risk associated with their presence may affect group composition, group size, movement patterns, and habitat use of prey species. The removal of predators, or their reintroduction following long periods of absence, equally can have profound impacts on their prey, triggering ecological cascades and ultimately shaping the biota of e...

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 pr...

Study shark ‘Demon’, demonstrating signficant change in the lower three quarters of the trailing edge. Despite having a large injury to the trailing ege of the dorsal fin, the fin identification can still be matched by using the shape of the leading edge and the top quarter of the fin. (TIF)

A dead, mature male leatherback turtle was sighted at Danger Point, Gansbaai on South Africa's south-west coast. Leatherback turtle sightings are rare along this coastline although the site lies between two areas of known aggregation; a tropical breeding area to the east and the highly productive Benguela upwelling ecosystem foraging area to the we...

White shark displaying damage to the dorsal fin as a result of SPOT tag deployment breaks the water at Gansbaai, South Africa during a Marine Dynamics cage diving trip. Photo courtesy of Michelle Wcisel, Marine Dynamics. (TIF)

We present 15 individual cases of sub-adult white sharks that were SPOT tagged in South Africa from 2003-2004 and have been re-sighted as recently as 2011. Our observations suggest SPOT tags can cause permanent cosmetic and structural damage to white shark dorsal fins depending on the duration of tag attachment. SPOT tags that detached within 12-24...

A live Indo-Pacific humpback dolphin (Sousa chinensis) with two bite wounds resulting from a great white shark (Carcharodon carcharias) encounter was observed from the commercial whale-watching vessel, Whale Whisperer, in Gansbaai on 23 and 24 August 2006. The most severe wound was to the dolphin's left flank area, the other to the anterior portion...