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Filter Total Items: 3374

Serrasalmidae — Piranhas and Pacus

The family Serrasalmidae is a morphologically and ecologically diverse group of South American freshwater fishes consisting of 16 genera and about 91 valid species. This chapter is a summary of the current state of knowledge on serrasalmid taxonomy, species richness, and ecology, and provides an identification key to the genera and references to relevant literature for species-level identification
Authors
Leo Nico, Michel Jegu, Marcelo C Andrade

Investigating seagrass in Toxoplasma gondii transmission in Florida (Trichechus manatus latirostris) and Antillean (T. m. manatus) manatees

Toxoplasma gondii is a feline protozoan reported to cause morbidity and mortality in manatees and other marine mammals. Given the herbivorous nature of manatees, ingestion of oocysts from contaminated water or seagrass is presumed to be their primary mode of infection. The objectives of this study were to investigate oocyst contamination of seagrass beds in Puerto Rico and determine the seropreval
Authors
Heidi M. Wyrosdick, Richard W. Gerhold, Chunlei Su, Antonio A. Mignucci-Giannoni, Robert K. Bonde, Alycia Chapman, Carla Riviera-Perez, Jessica Martinez, Debra L. Miller

Effects of host injury on susceptibility of marine reef fishes to ectoparasitic gnathiid isopods

The importance of the role that parasites play in ecological communities is becoming increasingly apparent. However much about their impact on hosts and thus populations and communities remains poorly understood. A common observation in wild populations is high variation in levels of parasite infestation among hosts. While high variation could be due to chance encounter, there is increasing eviden
Authors
William G. Jenkins, Amanda W.J. Demopoulos, Paul C. Sikkel

Field practices: Assessing tiger population dynamics using photographic captures

From these histories, capture frequency statistics and estimates of capture probabilities can be derived.
Authors
K. Ullas Karanth, James D. Nichols, Abishek Harihar, Dale Miquelle, N. Samba Kumar, Robert Dorazio

Concepts and practices: Estimating abundance of prey species using hierarchical model-based approaches

Tigers predominantly prey on large ungulate species, such as sambar (Cervus unicolor), red deer (Cervus elaphus), gaur (Bos gaurus), banteng (Bos javanicus), chital (Axis axis), muntjac (Muntiacus muntjak), wild pig (Sus scrofa), and bearded pig (Sus barbatus). The density of a tiger population is strongly correlated with the density of such prey species (Karanth et al. 2004). In the absence of di
Authors
Robert Dorazio, N. Samba Kumar, Andy Royle, Arjun M. Gopalaswamy

Concepts: Integrating population survey data from different spatial scales, sampling methods, and species

Conservationists and managers are continually under pressure from the public, the media, and political policy makers to provide “tiger numbers,” not just for protected reserves, but also for large spatial scales, including landscapes, regions, states, nations, and even globally. Estimating the abundance of tigers within relatively small areas (e.g., protected reserves) is becoming increasingly tra
Authors
Robert Dorazio, Mohan Delampady, Soumen Dey, Arjun M. Gopalaswamy

Advancing mangrove macroecology

Mangrove forests provide a wide range of ecosystem services to society, yet they are among the most anthropogenically impacted coastal ecosystems in the world. In this chapter, we discuss and provide examples for how macroecology can advance our understanding of mangrove ecosystems. Macroecology is broadly defined as a discipline that uses statistical analyses to investigate large-scale, universal
Authors
Victor H. Rivera-Monroy, Michael J. Osland, John W. Day, Santanu Ray, Andre S. Rovai, Richard H. Day, Joyita Mukherjee

Timing of warm water refuge use in Crystal River National Wildlife Refuge by manatees—Results and insights from Global Positioning System telemetry data

Managers at the U.S. Fish and Wildlife Service Crystal River National Wildlife Refuge (CRNWR) desire to update their management plan regarding the operation of select springs including Three Sisters Springs. They wish to refine existing parameters used to predict the presence of federally threatened Trichechus manatus latirostris (Florida manatee) in the springs and thereby improve their manatee m
Authors
Daniel H. Slone, Susan M. Butler, James P. Reid, Catherine G. Haase

An expert elicitation process to project the frequency and magnitude of Florida manatee mortality events caused by red tide (Karenia brevis)

Red tides (blooms of the harmful alga Karenia brevis) are one of the major sources of mortality for the Florida manatee (Trichechus manatus latirostris), especially in southwest Florida. It has been hypothesized that the frequency and severity of red tides may increase in the future because of global climate change and other factors. To improve our ecological forecast for the effects of red tides
Authors
Julien Martin, Michael C. Runge, Leanne J. Flewelling, Charles J. Deutsch, Jan H. Landsberg

A spatial approach to combatting wildlife crime

Poaching can have devastating impacts on animal and plant numbers, and in many countries has reached crisis levels, with illegal hunters employing increasingly sophisticated techniques. Here, we show how geographic profiling – a mathematical technique originally developed in criminology and recently applied to animal foraging and epidemiology – can be adapted for use in investigations of wildlife
Authors
Sally C. Faulkner, Michael C.A. Stevens, Stephanie S. Romañach, Peter A. Lindsey, Steven C. LeComber

Modeling the compensatory response of an invasive tree to specialist insect herbivory

The severity of the effects of herbivory on plant fitness can be moderated by the ability of plants to compensate for biomass loss. Compensation is an important component of the ecological fitness in many plants, and has been shown to reduce the effects of pests on agricultural plant yields. It can also reduce the effectiveness of biocontrol through introduced herbivores in controlling weedy invas
Authors
Bo Zhang, Xin Liu, Donald L. DeAngelis, Lu Zhai, Min B. Rayamajhi, Shu Ju

eDNAoccupancy: An R package for multi-scale occupancy modeling of environmental DNA data

In this article we describe eDNAoccupancy, an R package for fitting Bayesian, multi-scale occupancy models. These models are appropriate for occupancy surveys that include three, nested levels of sampling: primary sample units within a study area, secondary sample units collected from each primary unit, and replicates of each secondary sample unit. This design is commonly used in occupancy surveys
Authors
Robert Dorazio, Richard A. Erickson