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Current research focuses on the community ecology of mangrove fishes as well as the foraging behavior and ecology of marine predators, particularly sharks, and how they interact with their prey and the physical environment. Projects:
CURRENT PROJECTS White Shark Predatory Behavior
 Boat in fog Brief Overview NOTE: The Seal Island work described below reports on over 2,500 natural predatory attacks by white sharks on Cape fur seals. It is a shared result of an 8-year collaboration among R. Aidan Martin, the principal investigator of this project, Chris Fallows & Rob Lawrence, South African naturalists who discovered and opened the Seal Island site, and myself, with the gracious help of other people, as cited in context. During the winter, white sharks visit Seal Island to predate on Cape
fur seals. About 48% of surface attacks on Cape fur seals result
in successful kills. Attack frequency is high, averaging 6.68
per day, with as many as 43 recorded in a single day. Sharks attack
seals on the surface via a sudden vertical rush, which propels predator
and prey out of the water in an awesome display of power and acrobatic
prowess. White sharks appear to hunt solitary juvenile Cape fur seals
near their primary entry and exit point early in the morning, when
light levels are low. Stalking is conducted from near the bottom,
from sufficient depth to remain undetected during approach, and the
attack launched vertically.
This strategy
maximizes a shark's chance of catching
a seal unaware, resulting in a fatal
or incapacitating
initial strike. Stealth and
ambush are key elements in the white shark's predatory strategy.
Further, recognizable individual white sharks display distinct predoatry
strategies and some enjoy a predatory success rate of roughly 80%. For more information about white shark predatory behavior see
Since predatory events and seal movements at Seal Island are greatest at sunrise, I wondered whether we were seeing the tail end of nocturnal activity. Experiments using infrared video imaging demonstrated that both seals and white sharks can be detected in darkness by their thermal signatures and helped document that seal movement about the Island is greater at night than during the day.
Some 300 individual white sharks have been catalogued to date, including numerous re-sightings over separate days and years. Accumulated data is beginning to show that white sharks at Seal Island stay for short periods of time, many of the same individual sharks return year after year, and that numerous identifiable sharks appear to come and go together in groups of two to six. Group constitution appears to be constant from year-to-year and threat interactions among group members is low (suggesting well-established, stable social hierarchies), but occurs occasionally between members of different groups. Social hierarchies are stabilized and maintained largely through discrete behaviors, ranging from subtly synchronized swimming to overt displays. Many of these displays are defined and illustrated in R. Aidan Martin's book, Field Guide to the Great White Shark (available at Elasmo-Research) Conferences:
Publications:   
Shark Ecology of the Indian OceanAssessing the life-history and ecology of shark species inhabiting oceanic atolls within the Indian Ocean (with Chris Fallows and Dr. John Stevens) Brief overview:  Oceanic Whitetip The remote oceanic atolls and sea mounts of the Indian Ocean support a high diversity of elasmobranchs; however the biology and ecology of these animals are inadequately documented and the growing demand for shark fins has led to an increase in long-lining for sharks in these areas. In collaboration with Chris Fallows and Dr. John Stevens of CSIRO Marine Laboratory in Australia, shark surveys are being conducted at specific Indian Ocean atolls and sea mounts to document the shark species encountered, determine their population dynamics, describe their habitat utilization and identify areas that are important for their survival, such as nursery grounds. Publications:
Elasmobranch OsmoregulationReview of osmoregulation in freshwater and marine elasmobranchs. Brief overview:  ReefWalk Elasmobranchs are predominantly marine, although some 10% are estuarine, 2% are euryhaline, and 1% are obligate in fresh water. Studies of osmoregulation in elasmobranchs have been reported in the literature over the last seventy-five years; however, there have been significant advances in our understanding of the mechanisms underlying elasmobranch osmoregulation in just the past decade. This study provides a broad review of osmoregulation in elasmobranchs and recommends future directions for applied research that has particular significance for fish biologists, behaviourists and ecologists .  Lemon Shark Conferences:
Publications: Balancing food and refuge requirements across a subtropical marine ecotone: an assessment of nearshore fish distribution, diet and predation risk
A shark swims off with a research tag Neil's dissertation research focuses on determining the distributional patterns and foraging behaviors of mangrove fishes in seagrass beds in relation to their food availability and risk from predators to provide further insights into how animals will react to ecosystem changes, which has important implications for their management and conservation.
Dissertation Overview: 
Seine net sampling is used to characterize the seagrass fishes  Careful non-lethal stomach eversion is performed on a lemon shark to identify their prey  A juvenile gray snapper caught by seine sampling: an important prey item for predators of the mangroves and seagrass beds  The project is part of a collaboration with Biscayne National Park Balancing food and refuge requirements across a subtropical marine ecotone: an assessment of nearshore fish distribution, diet and predation risk. Coastal habitats such as mangroves and seagrass beds are among the most diverse and productive systems in the world. However, they are also amongst the most critically endangered due to anthropogenic modifications such as pollution and habitat destruction. Therefore, there are important scientific and economic reasons to determine how and why commercially and ecologically important organisms are distributed in these habitats. Mangroves and seagrass habitats are thought to function as nursery habitats for juvenile fishes providing food and refuge from predators, yet few studies have (1) examined the compositions and distributional patterns of fishes across seagrass beds in relation to mangrove proximity and (2) considered how food availability and predation risk influence fish foraging patterns across these habitats. Biscayne Bay provides a great opportunity to study fish habitat use of seagrass beds adjacent to mangroves. For PhD work, research will be conducted in Biscayne Bay to (1) characterize the fish assemblage inhabiting the seagrass beds along the shorelines of Biscayne Bay, (2) determine if and how fish distributional patterns in the seagrass beds vary with proximity to mangroves and (3) explore if these patterns are influenced by food availability and predation risk. This will be accomplished sequentially by (1) determining the composition and spatiotemporal abundance and diversity patterns of fishes and invertebrates inhabiting the Bay’s seagrass beds, (2) establishing if these patterns differ close to versus far from the mangroves, (3) identifying and examining how the dominant & commercially important reef fish and their prey are distributed across a distance gradient extending from the mangroves in to seagrass habitat, and (4) evaluating if and how predation risk influences these distributional patterns. This will be achieved through a sequence of complementary field observation, field manipulation and laboratory studies based in Florida.
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Predation Sequence
