Constructing captive ecology at the aquarium: Hierarchy, care, violence, and the limits of control

In a time of accelerating ecological crises, captive care performed by zoos and aquariums increasingly plays a central and controversial role in attempts to resuscitate species and ecosystems rapidly disappearing from the planet. Here I use the Giant Pacific octopus ( Enteroctopus dofleini) exhibit at the Vancouver Aquarium to examine practices involved in capture and captive care at a prominent Canadian institution. As I trace how octopuses come to the Aquarium and how people work to keep them alive and healthy in this environment, I examine the complex ways violence and domination interact with care practices. Centering octopuses and their material relations in this analysis thus allows me to connect everyday care practices to systems of governance and extraction that support captive ecologies and also generate the categories used in care. Through this investigation, I find that pastoral power organizes care practices at the Vancouver Aquarium and maintains anthropocentric order in this space. Slow violence here results from the imperfect replacement of lifegiving relations, and the nature of this harm is shaped by different beings’ relationships to anthropocentric order. Hierarchical categorizations structure care practices here, and when care directed at keeping animals healthy fails, slow violence often becomes acute. Elusiveness best characterizes how octopuses confound attempts to know and care for them within this anthropocentric power structure. The theoretical lens and language I offer seeks to describe moments of rupture in anthropocentric power without romanticizing animal endangerment as liberation or (conversely) accepting the logic that harm in captivity can only diminish if care improves. Through this work, I showcase both the violence and possibilities embedded in different ways of living and relating with ecological others amidst crisis.

Design of experimental food patches to measure foraging intensity for octopus: a case study with the giant Pacific octopus Enteroctopus dofleini

ABSTRACT In a study of the foraging behaviour of the giant Pacific octopus Enteroctopus dofleini, we designed two types of experimental food patches to measure habitat preferences and perceptions of predation risk. The first patch successfully measured giving-up densities (GUDs), confirmed by octopus prey presence and higher foraging at sites with historically greater octopus presence. However, nontarget foragers also foraged on these experimental food patches. Our second floating patch design successfully excluded nontarget species from subtidal patches, and from intertidal patches at high tide, but allowed for foraging by E. dofleini. The second design successfully measured GUDs and suggested that octopus preferred foraging in a subtidal habitat compared to an intertidal habitat. We ascribe the higher GUD in the intertidal habitat to its higher predation risk relative to the subtidal habitat. The second patch design seems well suited for E. dofleini and, in conjunction with a camera system, could be used to provide behavioural indicators of the octopus's abundance, perceptions of habitat quality and predation risk.

Diet of endangered Steller sea lions (Eumetopias jubatus) in the Aleutian Islands: new insights from DNA detections and bioenergetic reconstructions

The endangered western stock of Steller sea lion (Eumetopias jubatus (Schreber, 1776)) still declines in the western Aleutian Islands and accurate diet information is vital to test leading hypotheses. We undertook the first bioenergetic diet reconstruction using both molecular and hard part prey identifications from >600 scats collected in March–April 2008 and 2012. Atka mackerel (Pleurogrammus monopterygius (Pallas, 1810)) remained a primary prey (17%–27% by energy), but large (mean 60 cm) Pacific cod (Gadus macrocephalus Tilesius, 1810) also emerged as important prey (20%–24%) in a more diverse diet than previously reported, with Cottidae and smooth lumpsucker (Aptocyclus ventricosus (Pallas, 1769)) also contributing ∼10%. DNA detections highlighted a potentially important and previously underestimated prey, giant Pacific octopus (Enteroctopus dofleini (Wülker, 1910) (diet contribution 2%–15%, dependent on prey size assumptions). Although 504 unique DNA identifications resulted in significant increases for cephalopods, Pacific cod, and smooth lumpsucker, hard part alone species rankings were similar to composite ones and bioenergetic species rankings similar to occurrence-based ones. Retention or regurgitation of large cephalopod beaks, the removal of large cod heads, and skeletal fragility of lumpsuckers may explain these differences. DNA identifications provide valuable comparative and complementary prey occurrence data for pinnipeds, but composite diet estimates are optimal.