Effects of intense storm events on dolphin occurrence and foraging behavior

Abstract

As storms become increasingly intense and frequent due to climate change, we must better understand how they alter environmental conditions and impact species. However, storms are ephemeral and provide logistical challenges that prevent visual surveys commonly used to understand marine mammal ecology. Thus, relatively little is known about top predators’ responses to such environmental disturbances. In this study, we utilized passive acoustic monitoring to characterize the response of bottlenose dolphins to intense storms offshore Maryland, USA between 2015 and 2017. During and following four autumnal storms, dolphins were detected less frequently and for shorter periods of time. However, dolphins spent a significantly higher percentage of their encounters feeding after the storm than they did before or during. This change in foraging may have resulted from altered distributions and behavior of their prey species, which are prone to responding to environmental changes, such as varied sea surface temperatures caused by storms. It is increasingly vital to determine how these intense storms alter oceanography, prey movements, and the behavior of top predators.

The ACCOBAMS survey initiative: the first synoptic assessment of cetacean abundance in the Mediterranean Sea through aerial surveys

“…In a line transect distance sampling framework, the probability of detecting an object is a function of many factors other than distance of the object from the track-line, including group-size, species and habitats, as well as sea state (e.g., Holt and Cologne, 1987;Thomas et al, 2012;Fandel et al, 2020). Numerous studies have demonstrated that detection varies among species, over time, and among habitats, and there may be serious consequences when this variability is ignored.…”

Sounding the Call for a Global Library of Underwater Biological Sounds

“…PAM is already used for a multitude of biological applications. Examples include monitoring, characterizing and delineating underwater soundscapes, and investigating aquatic communities (e.g., Desjonquères et al, 2015;Erbe et al, 2015;Menze et al, 2017;Mooney et al, 2020;Stanley et al, 2021); documenting the distribution and migration patterns of the great whales (e.g., Risch et al, 2014;Tsujii et al, 2016;Davis et al, 2020;Warren et al, 2021); characterizing the spatial and temporal responses of fish choruses to environmental drivers like temperature, salinity, lunar phase, tide, and time of sunset (e.g., Barrios, 2004;Rountree et al, 2006;Parsons, 2010;Straight et al, 2015;Rice et al, 2016;McWilliam et al, 2017;Parsons et al, 2016;Karaconstantis et al, 2020;Linke et al, 2020); understanding how animals change their behavior and distribution in response to climate change (Gordon et al, 2018), anthropogenic noise sources (e.g., Thompson et al, 2013;Cerchio et al, 2014;Erbe et al, 2019;Meekan et al, 2021), algal blooms (e.g., Rycyk et al, 2020) and extreme weather events like hurricanes (e.g., Locascio and Mann, 2005;Fandel et al, 2020;Boyd et al, 2021;Schall et al, 2021); understanding how prey change their sound production rates or behaviors with the presence of predators (e.g., Luczkovich and Keusenkothen, 2007;Hughes et al, 2014;Bailey et al, 2019;Burnham and Duffus, 2019); and how noise and propagation conditions can affect communication spaces (e.g.,…”

An Expert Elicitation of the Effects of Low Salinity Water Exposure on Bottlenose Dolphins

“…However, globally, a number of studies have documented epidermal and biochemical changes associated with prolonged low salinity exposure (in both free swimming and stranded dolphins), including skin lesions, electrolyte imbalance, microbial infection and death [32][33][34][35][36][37][38], in addition to a disrupted prey environment affecting foraging [39]. In addition, data exist on behavioral and physiological responses in dolphins when water salinity is varied in a controlled manner or through natural events (i.e., hurricanes, floods, entrapments) [26,32,40] but die-offs have been associated with such instances [24,33,34].…”