ALBERT

Description: Significance Assessing change in Southern Ocean ecosystems is challenging due to its remoteness. Large-scale datasets that allow comparison between present-day conditions and those prior to large-scale ecosystem disturbances caused by humans (e.g., fishing/whaling) are rare. We infer the contemporary offshore foraging distribution of a marine predator, southern right whales (n = 1,002), using a customized stable isotope-based assignment approach based on biogeochemical models of the Southern Ocean. We then compare the contemporary distributions during the late austral summer and autumn to whaling catch data representing historical distributions during the same seasons. We show remarkable consistency of mid-latitude distribution across four centuries but shifts in foraging grounds in the past 30 y, particularly in the high latitudes that are likely driven by climate-associated alterations in prey availability. Abstract Assessing environmental changes in Southern Ocean ecosystems is difficult due to its remoteness and data sparsity. Monitoring marine predators that respond rapidly to environmental variation may enable us to track anthropogenic effects on ecosystems. Yet, many long-term datasets of marine predators are incomplete because they are spatially constrained and/or track ecosystems already modified by industrial fishing and whaling in the latter half of the 20th century. Here, we assess the contemporary offshore distribution of a wide-ranging marine predator, the southern right whale (SRW, Eubalaena australis), that forages on copepods and krill from ~30°S to the Antarctic ice edge (〉60°S). We analyzed carbon and nitrogen isotope values of 1,002 skin samples from six genetically distinct SRW populations using a customized assignment approach that accounts for temporal and spatial variation in the Southern Ocean phytoplankton isoscape. Over the past three decades, SRWs increased their use of mid-latitude foraging grounds in the south Atlantic and southwest (SW) Indian oceans in the late austral summer and autumn and slightly increased their use of high-latitude (〉60°S) foraging grounds in the SW Pacific, coincident with observed changes in prey distribution and abundance on a circumpolar scale. Comparing foraging assignments with whaling records since the 18th century showed remarkable stability in use of mid-latitude foraging areas. We attribute this consistency across four centuries to the physical stability of ocean fronts and resulting productivity in mid-latitude ecosystems of the Southern Ocean compared with polar regions that may be more influenced by recent climate change.

Description: Vibrios are rod-shaped bacteria, and are a functionally and phylogenetically diverse grouping of Gram-negative microbes found widely in aquatic, estuarine, and marine habitats. Approximately a dozen Vibrio species are known to cause disease in humans, and infection is usually initiated from exposure to seawater or consumption of raw or undercooked seafood. Although a wide range of different bacterial species contain multiple chromosomes, Vibrio species are noted in that they possess two circular chromosomes. Bacteria of the genus Vibrio are commonly found in tropical and temperate coastal and estuarine waters. Vibrios are among the most common bacteria that inhabit surface waters throughout the world and are responsible for a number of severe infections both in humans and animals. Vibriosis is characterized by diarrhea, primary septicemia, wound infections, or other extraintestinal infections. Select strains of V. cholerae, V. parahaemolyticus, V. vulnificus, and V. alginolyticus are perhaps considered the most serious human pathogens from this genus. Two Vibrio species in particular, V. vulnificus and V. parahaemolyticus are significant foodborne human pathogens, and most frequently infections occur via the consumption of naturally contaminated shellfish produce. It is worth noting that these pathogens represent a significant cause of morbidity and mortality. For example, an estimated 80,000 people contract Vibrio infections each year in the United States, with a sizeable fraction originating from foodborne sources, such as consumption of raw or undercooked seafood produce. Recent data from the Centers for Disease Control and Prevention (CDC) in the United States have indicated that there has been a significant increase in reported infections associated with vibrios, particularly in the last two decades. The annual incidence of reported vibriosis per 100,000 population has increased significantly in the United States from 1996 to 2010, highlighting the importance of these pathogens from a clinical context. Calculations based upon probable incidence of vibriosis have estimated that V. vulnificus and V. parahaemolyticus are the first and third most costly marine-borne pathogens, costing $233 and $20 million, respectively. From a foodborne perspective V. vulnificus and V. parahaemolyticus represent the major pathogens from the Vibrio genus in terms of clinical impact and relevance, and as such this chapter is mostly concerned with these species. These taxa do not sustain prolonged presence in clinical or agricultural settings, where it would likely undergo human-induced selection for antibiotic resistance. As such, these bacteria represent a particularly interesting group of pathogens to study antibiotic resistance, as they provide a “snapshot” of resistance presumably acquired from environmental rather than clinical settings. Despite their public-health significance, strains of V. parahaemolyticus and V. vulnificus have not been extensively monitored for antimicrobial resistance, in contrast to enteric pathogens such as Salmonella or Campylobacter. Given their increasing incidence, global distribution, and severity of disease progression (especially V. vulnificus) it is critical to gain a better understanding of the antimicrobial susceptibility patterns of V. vulnificus and V. parahaemolyticus originating from the environment (Shaw et al., 2014). Data from such sources is invaluable, particularly from routine antimicrobial screening of large numbers of environmental and clinical Vibrio strains as it can provide effective baseline data for treatment purposes.