First autonomous recording of in situ dissolved oxygen from free-ranging fish

Abstract

Background: Biologging technology has enhanced our understanding of the ecology of marine animals and has been central to identifying how oceanographic conditions drive patterns in their distribution and behavior. Among these environmental influences, there is increasing recognition of the impact of dissolved oxygen on the distribution of marine animals. Understanding of the impact of oxygen on vertical and horizontal movements would be advanced by contemporaneous in situ measurements of dissolved oxygen from animal-borne sensors instead of relying on environmental data that may not have appropriate spatial or temporal resolution. Here, we demonstrate the capabilities of dissolved oxygen pop-up satellite archival tags (DO-PATs) by presenting the results from calibration experiments and trial deployments of two prototype tags on bluntnose sixgill sharks (Hexanchus griseus). Results:The DO-PATs provided fast, accurate, and stable measurements in calibration trials and demonstrated high correlation with vertical profiles obtained via traditional ship-borne oceanographic instruments. Deployments on bluntnose sixgill sharks recorded oxygen saturations as low as 9.4 % and effectively captured the oceanography of the region when compared with World Ocean Atlas 2013 values.Conclusions: This is the first study to use an animal-borne device to autonomously measure and record in situ dissolved oxygen saturation from non-air-breathing marine animals. The DO-PATs maintained consistency over time and yielded measurements equivalent to industry standards for environmental sampling. Acquiring contemporaneous in situ measurements of dissolved oxygen saturation alongside temperature and depth data will greatly improve our ability to investigate the spatial ecology of marine animals and make informed predictions of the impacts of global climate change. The information returned from DO-PATs is relevant not only to the study of the ecology of marine animals but will also become a useful new tool for investigating the physical structure of the oceans.

Research Priorities to Support Effective Manta and Devil Ray Conservation

“…New sensory systems can also be incorporated into existing telemetry devices. For example, fluorometers embedded into satellite tags can provide in situ measurements of phytoplankton fluorescence that can be used to calculate chlorophyll-a concentrations and to assess primary productivity levels alongside animal movement data (Lander et al, 2015), with additional dissolved oxygen sensors able to associate dive and oxygen profiles along with temperature and salinity measurements (Bailleul et al, 2015;Coffey and Holland, 2015). The use of "sonar tags" that are capable of recording prey field density concurrently with movement tracks would allow for detailed studies of mobulid movements and prey targeting, although this currently requires tag recovery (Lawson et al, 2015), which may limit applications to coastal species such as reef manta rays.…”

Diel patterns in swimming behavior of a vertically migrating deepwater shark, the bluntnose sixgill (Hexanchus griseus)

“…Based on physiological tolerances, organisms may alter their behavior in response to changing environmental conditions encountered during migration [6][7][8][9]. In the subtropical waters off Hawai'i, bluntnose sixgill sharks (Hexanchus griseus; hereafter referred to as sixgill sharks) undergo a distinct diel vertical migration descending to depths below 500 m during the day and ascending to 200-350 m during the night and encounter a wide range of temperatures (5-20˚C [10][11]) and dissolved oxygen conditions (9-85% saturation [12]; <60-200 μmol kg -1 [10]). Sixgill sharks appear to be highly tolerant of low dissolved oxygen, remaining in waters that are generally considered hypoxic (defined as <61 μmol kg -1 [13][14][15]) within the local oxygen minimum zone (OMZ) throughout their deeper, daytime distribution [10,12,16].…”

Towards the integration of animal‐borne instruments into global ocean observing systems

“…Furthermore, while this technology can provide key information on essential biodiversity variables (e.g. species distribution, physiology, movement, species interactions), animal-borne instruments (ABI) can now also provide essential ocean variables such as temperature, conductivity, light level, oxygen and chlorophyll (Bailleul, Vacquie-Garcia, & Guinet, 2015;Boehme et al, 2009;Coffey & Holland, 2015;Harcourt et al, 2019;Laidre, Heide-Jørgensen, Logsdon, Delwiche, & Nielsen, 2010;Teo et al, 2009). Therefore, integrating ABI can complement ocean observing platforms such as Argo floats, gliders and other autonomous vehicles to provide unique and cost-effective data from poorly sampled ocean regions (Block et al, 2016;Bograd, Block, Costa, & Godley, 2010;Fedak, 2004;Harcourt et al, 2019;Hays et al, 2016;Hussey et al, 2015;Roemmich et al, 2010;Roquet et al, 2014).…”

“…Therefore, integrating ABI can complement ocean observing platforms such as Argo floats, gliders and other autonomous vehicles to provide unique and cost-effective data from poorly sampled ocean regions (Block et al, 2016;Bograd, Block, Costa, & Godley, 2010;Fedak, 2004;Harcourt et al, 2019;Hays et al, 2016;Hussey et al, 2015;Roemmich et al, 2010;Roquet et al, 2014). For instance, ABI in the marine environment have been deployed on pinnipeds (Bailleul et al, 2015;Roquet et al, 2014), cetaceans (Laidre et al, 2010), marine turtles (Chambault et al, 2015(Chambault et al, , 2016McMahon et al, 2005;McMahon & Hays, 2006;Patel et al, 2018), sharks (Coffey & Holland, 2015;Payne et al, 2018), fish (Block, Costa, Boehlert, & Kochevar, 2002), flying seabirds (Wilson et al, 2002;Wilson & Vandenabeele, 2012), penguins (Charrassin, Park, Maho, & Bost, 2002;Sala, Pisoni, & Quintana, 2017) and sirenians (Hagihara et al, 2018). Animals can travel to regions that are relatively inaccessible to other ocean observing technologies.…”