Recruitment of larvae from the plankton is an important determinant of
community structure in marine systems. In populations of many marine species,
recruitment determines the basic demographic parameters of immigration, emigration,
and reproduction. Moreover, the effect of recruitment as an "ecological subsidy" can
determine the strength of interactions among species...
Ocean Acidification (OA) has emerged as a major threat to marine ecosystems, particularly regarding calcifying organisms. A growing body of literature describing laboratory investigations into pH stress indicates broadly deleterious effects for calcifiers, but responses vary greatly across taxa and can be influenced by variations in other environmental characteristics. Scaling...
The high productivity of Eastern Boundary Upwelling Ecosystems (EBUE), some of the most productive ecosystems in the globe, is attributed to the nutrient rich waters brought up through upwelling. Climate change scenarios for coastal upwelling systems, predict an intensification of coastal upwelling winds. Associated with intensification in upwelling are biogeochemical...
Most climate change predictions focus on the response of individual species to changing local conditions and ignore species interactions, largely due to the lack of a sound theoretical foundation for how interactions are expected to change with climate and how to incorporate them into climate change models. Much of the...
Dislodged macroalgae and seagrasses, also known as marine wrack, frequently wash into coastal ecosystems from the ocean and are potentially important ecological resources for biological communities. These!nutrient and organic matter subsidies may be especially important on sandy beaches, where little in situ primary productivity exists for higher trophic levels. To...
The influence of the physical environment on organisms has long been a subject of ecological research. But, the complex drivers of environmental variation, and the multiple scales at which this can occur, make studying this topic a difficult challenge. In rocky intertidal habitats, oceanographic- and climate-scale variability influence benthic communities...
Oceanic uptake of rising anthropogenic CO₂ emissions has caused the emergence of ocean acidification as a major threat to marine ecosystems worldwide. Along eastern boundary current systems, seawater is naturally acidified due to coastal upwelling of low pH seawater from depth. Compounded by ocean acidification, upwelling regions are expected to...
The multifaceted role of the environment in regulating the structure and dynamics of biological communities has long fascinated ecologists and motivated much debate and research. Now, in a time of accelerated global changes due to human impacts, the need to understand how the environment shapes communities has gained new urgency....
This dissertation investigates the context-dependency of species interactions between seagrass and macroalgae in upwelling-influenced estuaries. In all coastal systems, nutrient loading is multidirectional, resulting from mostly freshwater and marine inputs. The directionality of nutrient inputs may affect the rate of supply of organic matter to the system. In systems where...
Ecosystems are facing increasing threats from human related activities, such as overfishing, pollution, habitat destruction, species invasions, and diseases, among others. While oceanic islands provide natural laboratories to understand ecological and evolutionary process, they are also particularly vulnerable to these impacts, given their usual isolation from the mainland and the...
While community ecologists have traditionally focused on local-scale processes, it has become apparent that a broader perspective, which explores the community-level ramifications of material fluxes within and between ecosystems, is necessary to effectively evaluate bottom-up influences on community structure and dynamics. In this dissertation, I employed ecosystem principles to understand...
Human actions are pushing natural systems into states that have no historical precedent. In response, empirical and theoretical researchers are increasingly focused on developing ways to predict the responses of ecological systems to change. However, significant knowledge gaps remain, often leading to “ecological surprises” where observed impacts of global change...
This dissertation focuses on the evolutionary forces of genetic drift and gene flow in frog populations. The balance of these two forces and the force of mutation largely determine the amount of neutral genetic variation within populations as well as the degree of genetic similarity among populations. The stochastic evolutionary...
Invasive species are a growing global economic and ecological problem. Invasive Indo-Pacific lionfish (Pterois spp.) are known to have extreme negative effects on coral-reef communities in the Bahamas, so understating their distribution within and among reefs, what limits their local movements, and the effects they have on native prey species...
Many marine fish populations are severely declining due to over-fishing, loss of both juvenile and adult habitats, and accelerating environmental degradation. Fisheries management and the implementation of marine protected areas (MPAs) and other conservation tools are currently hindered by large gaps in knowledge about larval dispersal and its subsequent effects...
Biological invasions and climate change represent two preeminent threats to ecological communities and biodiversity, altering the distribution and abundance of species, disrupting existing species interactions and forming unprecedented ones, and creating novel ecological communities. Many of the most successful invasive species are also ecosystem engineers, species that physically modify the...
Biological invasions provide a unique opportunity to study the mechanisms that regulate community composition and ecosystem function. Invasive species that are also ecosystem engineers can substantially alter physical features in an environment, and this can lead to cascading effects on the biological community. Aquatic-terrestrial interface ecosystems are excellent systems to...