Search

In seagrass habitats, structural complexity influences predator foraging success and prey survival by moderating encounter rates and behaviors of predators and prey. Studies of the effects of structural complexity on predator–prey interactions typically vary seagrass shoot density, biomass, or architecture. Filamentous epiphytic algae commonly grow on seagrass blades and add structure to seagrasses, but the effect of epiphytes on the outcome of predator–prey interactions has rarely been explored. This study determined the relative effects of simulated seagrass epiphytes, eelgrass ( Zostera marina ) shoot density, and prey density on the foraging behaviors of a common predator, the juvenile giant kelpfish Heterostichus rostratus (Girard, 1854) and on escape responses of their prey, grass shrimp Hippolyte californiensis (Holmes, 1895). Juvenile giant kelpfish hunted for grass shrimp in a laboratory experiment in which two levels of grass shrimp density were crossed with three levels of structural complexity (low density artificial eelgrass, low density artificial eelgrass with artificial epiphytes, and high density artificial eelgrass). Increased structural complexity had variable effects on juvenile kelpfish activity levels, but enhanced their success at catching prey after detection, resulting in no net effect of structural complexity on the total number of prey captured. Grass shrimp made fewer escape attempts in high vs. low structural complexity, which may have enhanced kelpfish foraging success because kelpfish rarely pursued fleeing prey. Prey density did not influence kelpfish behaviors or the total amount of prey they consumed. These results suggest that it is important to consider how different forms of habitat complexity affect the mechanisms by which predators hunt for prey in structured marine habitats. [ABSTRACT FROM AUTHOR]

Seaweed-herbivore interactions are often mediated by environmental conditions, yet the roles of emerging anthropogenic stressors on these interactions are poorly understood. For example, chemical contaminants have unknown consequences on seaweed inducible resistance and herbivore response to these defenses despite known deleterious effects of contaminants on animal inducible defenses. Here, we investigated the effect of copper contamination on the interactions between a snail herbivore and a brown seaweed that displays inducible resistance to grazing. We examined seaweed inducible resistance and its effectiveness for organisms exposed to copper at two time points, either during induction or after herbivores had already induced seaweed defenses. Under ambient conditions, non-grazed tissues were more palatable than grazed tissues. However, copper additions negated the preference for non-grazed tissues regardless of the timing of copper exposure, suggesting that copper decreased both how herbivores initiated these inducible defenses and their subsequent effectiveness. Copper decreased stimulation of defenses, at least in part, by suppressing snail grazing pressure—the cue that turns inducible defenses on. Copper decreased effectiveness of defenses by preventing snails from preferentially consuming non-grazed seaweed. Thus, contaminants can potentially stress communities by changing seaweed-herbivore interactions mediated via inducible defenses. Given the ubiquity of seaweed inducible resistance and their potential influence on herbivores, we hypothesize that copper contamination may change the impact of these resistant traits on herbivores. [ABSTRACT FROM AUTHOR]

Identifying sites with refugial capacity can inform conservation efforts to assess the degradation status of global ecosystems (Keith et al., 2013), and it can guide landscape conservation planning (e.g., Moilanen, 2007). Although climate-change impacts are of mounting concern (e.g., Araújo et al., 2006; Scholze et al., 2006; Halsch et al., 2021), climate change is only one of many anthropogenic stressors contributing to biodiversity declines (Morris et al., 2020). Environmental stability is a key concept often applied when describing refugia for species and ecosystem persistence or resistance to change (Keppel et al., 2015, Morelli et al., 2020) under current and future climate change (McCullough et al., 2016). Keywords: amenazas; biodiversidad; cambio climático; cambio global; gestión y planificación estratégica; paisajes; sur de California; biodiversity; climate change; global change; landscapes; Southern California; strategic planning and management; threats; ; ; ; ; ; ; EN amenazas biodiversidad cambio climático cambio global gestión y planificación estratégica paisajes sur de California biodiversity climate change global change landscapes Southern California strategic planning and management threats 1 11 11 03/02/22 20220201 NES 220201 INTRODUCTION The specter of biodiversity loss due to human activities is widely recognized and well described in natural systems (Maxwell et al., 2016). [Extracted from the article]

The article presents ten simple rules for effective online outreach. Topics discussed include writing blog posts for newly published paper, need of formal planning mechanism for all online outreach projects, need of good content, and use of online social networking tools including Twitter and Facebook, to promote content, and collection of data.