Marine Biology Commons^™

Fishing And Fear Effects Interact To Shape Herbivory On Coral Reefs, Bethany M. Tilton

All HCAS Student Capstones, Theses, and Dissertations

Predation influences animal behavior and shapes ecological structure and function through lethal effects and fear effects. On coral reefs, fear effects can alter the distribution and intensity of herbivory by herbivorous reef fishes. This includes the browsing functional group, which potentially reverses macroalgal phase shifts and promotes reef recovery. Herbivory by multiple functional groups may increase on coral reefs through the use of NTZs (no-take zones) but few studies have examined the extent to which small-scale NTZs (< 0.5 km²) influence fear effects and perceived predator presence on reefs. This study aimed to determine whether fear effects on browsers on …

Fear Effects And Group Size Interact To Shape Herbivory On Coral Reefs, Andrew G. Bauman, Andrew S. Hoey, Glenn Dunshea, Jenny Fong, Ian Z. W. Chan, Peter A. Todd

Marine & Environmental Sciences Faculty Articles

1. Fear of predators (‘fear effects’) is an important determinant of foraging decisions by consumers across a range of ecosystems. Group size is one of the main behavioural mechanisms for mitigating fear effects while also providing foraging benefits to group members. Within coral reef ecosystems, fear effects have been shown to influence the feeding rates of herbivorous fishes, a key functional group that prevents macroalgal overgrowth. Yet, how fear effects and group size interact to shape macroalgal removal on coral reefs remains unclear.
2. Here, we conducted field-based experiments using models of a common piscivorous fish, the leopard coral grouper Plectropomus leopardus …

Assessing Predator Risk To Diadromous Fish Conservation In The Penobscot River Estuary, Lauri Leach

Electronic Theses and Dissertations

Successful conservation of pinnipeds in the northwest Atlantic has led to increasing populations of harbor (Phoca vitulina) and gray seals (Halichoerus grypus) in the Gulf of Maine. Seals are often perceived as predators and competitors for fish, and as a result, come into conflict with fisheries and fish conservation. Increasing numbers of seals have become a recent concern in the Penobscot River Estuary in Maine, as habitat restoration and diadromous fish conservation have been top priorities in this region for the past decade.

To understand how pinnipeds are responding to these efforts, as well as the risks they pose to …

Structure, Control, And Communication Of Collective Animal Behavior In Dynamic Environments, Ivan Ignacio Rodriguez-Pinto

FIU Electronic Theses and Dissertations

Collective behavior in animal aggregations is highly complex and spans multiple spatial scales, across a wide range of environmental conditions. In socially active fish, aggregation into schools is a widespread adaptation that confers a variety of safety benefits. The emergent patterns exhibited by collectively behaving fish schools may be influenced by biotic (i.e. predation) or abiotic (i.e. habitat complexity, turbidity) factors in the local environment. Our knowledge of the ways and extent to which environment variability affects schooling behavior at the collective level is currently limited. In this dissertation, I investigated whether environmental factors influenced the collective behavior of fish …

Changes In Prey Mortality: The Efects Of Multiple Predators And Temperature On California Mussels, Wesley Hull

Cal Poly Humboldt theses and projects

Organisms serve as prey to a variety of predators within natural systems, detecting threats through physical and chemical means. While predator feeding behavior is also affected by the presence of other predators, it is unclear whether differing modes of detection have similar effects on predator feeding behavior. In rocky intertidal zones in northern California, the California mussel (Mytilus californianus) is a competitively dominant foundation species consumed by a variety of predators. I quantified the individual and combined effects of ochre star (Pisaster ochraceus) and rock crab (Romaleon antennarium) predation on mussels by implementing mussel …

Fear Effects Associated With Predator Presence And Habitat Structure Interact To Alter Herbivory On Coral Reefs, Andrew G. Bauman, Jovena C. L. Seah, Fraser A. Januchowski-Hartley, Andrew S. Hoey, Jenny Fong, Peter A. Todd

Marine & Environmental Sciences Faculty Articles

Non-consumptive fear effects are an important determinant of foraging decisions by consumers across a range of ecosystems. However, how fear effects associated with the presence of predators interact with those associated with habitat structure remain unclear. Here, we used predator fish models (Plectropomus leopardus) and experimental patches of the macroalga Sargassum ilicifolium of varying densities to investigate how predator- and habitat-associated fear effects influence herbivory on coral reefs. We found the removal of macroalgal biomass (i.e. herbivory) was shaped by the interaction between predator- and habitat-associated fear effects. Rates of macroalgal removal declined with increasing macroalgal density, likely …

Indirect Legacy Effects Of An Extreme Climatic Event On A Marine Megafaunal Community, Robert Nowicki, Michael Heithaus, Jordan Thompson, Derek Burkholder, Kirk Gastrich, Aaron Wirsing

Marine & Environmental Sciences Faculty Articles

While extreme climatic events (ECEs) are predicted to become more frequent, reliably predicting their impacts on consumers remains challenging, particularly for large consumers in marine environments. Many studies that do evaluate ECE effects focus primarily on direct effects, though indirect effects can be equally or more important. Here, we investigate the indirect impacts of the 2011 “Ningaloo Niño” marine heatwave ECE on a diverse megafaunal community in Shark Bay, Western Australia. We use an 18‐year community‐level data set before (1998–2010) and after (2012–2015) the heatwave to assess the effects of seagrass loss on the abundance of seven consumer groups: sharks, …

Ecological Consequences Of Sea Star Wasting Disease: Non-Consumptive Effects And Trait-Mediated Indirect Interactions From Pisaster Ochraceus, Timothy Ian Mcclure

Cal Poly Humboldt theses and projects

Consumptive effects (CEs) of predators are an important factor in structuring biological communities, but further work is needed to understand how the interaction between spatial and temporal differences in predator density affects non-consumptive effects (NCEs) on prey. NCEs can cause indirect effects on food resources, known as trait-mediated indirect interactions (TMIIs), and thus can also affect community structure. However, few studies have considered the relationships between spatial and temporal predator density variation and the strength of NCEs and TMIIs in the natural environment. The ochre star Pisaster ochraceus is common predator of the herbivorous black turban snail Tegula funebralis, imposing …

The Effects Of Copper Exposure On Fish Locomotion And Predator-Prey Interactions, Tiffany N. Yanez

FIU Electronic Theses and Dissertations

This study determined the effects of the copper water quality criterion (WQC) by the EPA on [1] swimming performance and [2] predator-prey interactions of the Sailfin Molly, across a salinity gradient. Fish acclimated to FW (0 ppt) and 8-ppt saltwater were exposed to 11.3 and 8.44 µg/L Cu for 96 h, respectively. At the end of the exposures, fish swimming performance was determined by using the critical swimming speed, U_crit, the speed at which a fish cannot longer maintain position in the water column. U_critwas then measured again after a 4-week depuration period to determine if …

Caged Oysters Still Get Scared: Predator Presence And Density Influence Growth In Oysters, But Only At Very Close Ranges, Stephen Gosnell J., Kali Spurgin, Erica A. Levine

Publications and Research

Two common forms of variation that may influence consumptive and non-consumptive effects differently are how the biomass of predators is allocated among individual predators (e.g., several small vs few large predators) and how predators are spaced throughout a community. We analyzed how varying the presence, biomass (density, size, and total biomass), and distance to crown conchs (Melongena corona) impacted growth in eastern oysters (Crassostrea virginica) grown in field conditions. The presence of predators decreased growth (new shell added and mass) and increased shell thickness in a 58-day experiment. Although these effects were more pronounced as predator …

Top Predators Negate The Effect Of Mesopredators On Prey Physiology, Maria Palacios, Shaun S. Killen, Lauren E. Nadler, James R. White, Mark I. Mccormick

Marine & Environmental Sciences Faculty Articles

1. Predation theory and empirical evidence suggest that top predators benefit the survival of resource prey through the suppression of mesopredators. However, whether such behavioural suppression can also affect the physiology of resource prey has yet to be examined.
2. Using a three‐tier reef fish food web and intermittent‐flow respirometry, our study examined changes in the metabolic rate of resource prey exposed to combinations of mesopredator and top predator cues.
3. Under experimental conditions, the mesopredator (dottyback, Pseudochromis fuscus ) continuously foraged and attacked resource prey (juveniles of the damselfish Pomacentrus amboinensis ) triggering an increase in prey O2 uptake by 38 ± …

Shifts In Attack Behavior Of An Important Kelp Forest Predator Within Marine Reserves, J. S. Berriman, M. C. Kay, D. C. Reed, A. Rassweiler, D. A. Goldstein, William G. Wright

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Marine reserves have become increasingly valuable tools with which to manage ecosystems. These reserves consistently restore populations of top predators, often reducing availability of their favored prey. We hypothesized that such prey reduction in reserves causes protected predators to alter their attack behavior to include less palatable prey, potentially amplifying top-down effects on community structure. To test this hypothesis, we presented the relatively unpalatable sea hare Aplysia californica to freely foraging spiny lobsters Panulirus interruptus in 4 marine no-take reserves, each paired with an adjacent fished area. We found that lobsters only attacked sea hares inside reserves, where lobster density …

The Effects Of Refuge On Escape Responses Of Two Caribbean Goby Species, Russell P. Dauksis

Senior Honors Projects

The Effects of Refuge Abundance on Escape Responses of the Bridled Goby (Coryphopterus glaucofraenum)

Russell P. Dauksis

Major

Marine Biology

Advisor

Dr. Graham Forrester

Advisor Department

Natural Resources Science

Date

5-2012

Keywords

Escapology, marine ecology, functional morphology, animal behavior, predator-prey interactions, Bridled Goby, Coryphopterus glaucofraenum

Abstract

Interactions between predators and prey species are arguably the most pervasive and important events in ecology. Predators have strong effects on the distribution and abundance of prey in virtually all environments. In the long-term, it is therefore hardly surprising that selective mortality imposed by predators has shaped a wide array of prey behaviors …

Stalked Crinoid Locomotion, And Its Ecological And Evolutionary Implications, Tomasz K. Baumiller, Charles G. Messing

Marine & Environmental Sciences Faculty Articles

In the past two decades, much direct evidence has been gathered on active crawling by stalked crinoids, a group generally thought to be sessile. Detailed descriptions of crawling mechanics of isocrinids in aquaria revealed only exceedingly slow movements (~0.1 mm sec^-1). Crawling at such speeds severely restricted the range of roles that this behavior could play in stalked crinoid biology and, consequently, in its potential impact on their ecology and evolutionary history. Here, we provide evidence collected in situ by submersible near Grand Bahama Island at a depth of 420 m for a different mode of crawling in …