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The non-native pet trade contributes directly to species invasions, thereby threatening wildlife. Biological invasions influence environmental change, resulting in species extinctions and biodiversity loss. To mitigate the pet trade invasion risk, interventions are required to prevent trade in non-native animals with high invasion potential, impulse or ill-informed purchases of non-native pets by individuals who may release these animals, and the deliberate release of non-native animals by pet owners. Interventions are also required to prevent the establishment of non-native animals that have been released by pet owners (e.g., euthanasia). The successful implementation of these interventions depends on the support of pet owners and the public in the form of political support for, and compliance with, interventions. In 2017–2018, using both mail and online surveys, we measured the support of 1,171 members of the public and 550 owners of non-native pets in Florida, USA, for 7 different interventions to mitigate the pet trade invasion risk, and we investigated determinants of this support. We found that individuals' support for interventions depended on their concern related to the invasion risks associated with the pet trade, trust in government to manage the pet trade, perceptions of how effective interventions would be in mitigating the pet trade invasion risk, and demographic characteristics. Support for interventions differed across pet owners and the public. Educating pet owners about the traits and cost of care for non-native animals and providing them with options to relinquish unwanted pets may reduce the pet trade invasion risk. Engaging the pet trade in the design of interventions to mitigate invasion risks is likely important to attain voluntary compliance with these interventions. The effectiveness of interventions also depends on enforcement by agencies. Implementing interventions that effectively reduce the pet trade invasion risk is important to protect native and endangered wildlife. © 2020 The Wildlife Society.  相似文献   
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The interplay between mangroves and saltmarshes at the temperate to subtropical transition in Florida results in dramatic changes to the appearance of the coastal landscape. In the 1980s, freezes killed entire mangrove forests dominated by black mangroves, Avicennia germinans (L.). Following the freezes, saltmarshes dominated by smooth cordgrass, Spartina alterniflora Loisel, revegetated the intertidal zone. After a decade of mild winters, however, mangroves are beginning to reclaim the area. The rate of mangrove expansion was determined by comparing aerial photography (change from 1995 to 1999), and from monitoring transects (over a 3 year period) on three of the Cedar Keys, Florida (Lat. 29°08′). The rate of mangrove expansion varied among islands, and the mechanism of expansion ranged from propagule-trapping by saltmarshes along the edges of mangrove clumps to widespread dispersal and growth of existing or newly imported propagules. A freeze occurred during the study, which may have set back mangrove expansion by defoliating mangrove trees and resetting mangrove reproduction. Mangrove expansion was projected to take 20–30 years for complete seedling cover. Given the possibility of global climate change and its potential influence on the distribution of coastal vegetation, the timeframes and implications to coastal wetland ecosystems involved in this regular interplay will provide valuable baseline information for future studies.  相似文献   
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The NASA Experimental Advanced Airborne Research Lidar (EAARL), a temporal waveform-resolving, airborne, green wavelength LIDAR (light detection and ranging), is designed to measure the submeter-scale topography of shallow reef substrates. Topographic variability is a prime component of habitat complexity, an ecological factor that both expresses and controls the abundance and distribution of many reef organisms. Following the acquisition of EAARL coverage over both mid-platform patch reefs and shelf-margin bank reefs within Biscayne National Park in August 2002, EAARL-based optical indices of topographic variability were evaluated at 15 patch reef and bank reef sites. Several sites were selected to match reefs previously evaluated in situ along underwater video and belt transects. The analysis used large populations of submarine topographic transects derived from the examination of closely spaced laser spot reflections along LIDAR raster scans. At all 15 sites, each LIDAR transect was evaluated separately to determine optical rugosity (Rotran), and the average elevation difference between adjacent points (Av(Eap)). Further, the whole-site mean and maximum values of Rotran and Av(Eap) for the entire population of transects at each analysis site, along with their standard deviations, were calculated. This study revealed that the greater habitat complexity of inshore patch reefs versus outer bank reefs results in relative differences in topographic complexity that can be discerned in the laser returns. Accordingly, LIDAR sensing of optical rugosity is proposed as a complementary new technique for the rapid assessment of shallow coral reefs.  相似文献   
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Synopsis Eugenie Clark is an ichthyologist with a talent for communicating about marine life. Her life had three principal periods, (1) studies under Charles Breder, Carl Hubbs, Lester Aronson and Myron Gordon, (2) directorship of the Cape Haze Marine Laboratory sponsored by the Vanderbilts, and (3) professorship and inspired teaching at the University of Maryland. Genie proved that sharks have surprising learning abilities and that, contrary to popular opinion, none are vicious killers. During her studies on reproductive behavior, territoriality, and ecology of tropical marine sand-dwelling fishes of the Caribbean and Red seas, among many other phenomena, she discovered the cross-fertilizing hermaphroditeSerranus subligarius, the Moses and peacock soles producing toxins that repel sharks and other predators, and sharks sleeping in underwater caves in Mexico and Japan. She combined a love for swimming and diving with the study of marine fishes - from hard-hat diving and snorkeling to using SCUBA and submersibles. Professor emerita since 1992, she has ridden whale sharks and participated in dives using submersibles to 3 600 m depths. She is a recipient of over 25 honors and awards, participated in 24 television specials, and the current IMAX film on sharks. She is the author of theLady with a Spear andThe Lady and the Sharks which are of considerable popular fame.  相似文献   
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Abstract. The widespread suppression of fire during the 20th century has created extensive areas of fire-prone ecosystems that are in long-unburned condition. Plant species of flatwoods and scrubby flatwoods (= oak scrub) in the southeastern USA possess adaptations that facilitate resprouting, clonal spread, or seeding following fire. While the majority of the woody species of these associations can persist for long periods without fire, fire suppression reduces the populations of ephemeral herbs. Long-unburned (> 35 yr) flatwoods and scrubby flatwoods were burned after five annual vegetation censuses. Both stands were resampled five times over a >8-yr recovery period. One recently burned (<20 yr) flatwoods and two recently burned scrubby flatwoods were censused prior to fire and were recensused over a 5-yr or 11-yr period following fire depending on the stand. In spite of the variety of recovery strategies and time since fire, there were limited changes in the compositions and structures of post-burn stands compared to their preburn states. Detrended Correspondence Analysis showed that recently burned stands returned to preburn states within 1–2 yr. However, the reintroduction of a single fire to long-unburned stands did not restore the populations of herbs typical of recently burned stands. Our results suggest that a single fire may not be effective in restoring flatwoods and scrubby flatwoods that have experienced fire suppression to states more characteristic of recently burned stands.  相似文献   
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