Thomas Okey

University of Victoria, Environmental Studies, Adjunct

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Centering relationships to place for more meaningful research and engagement

Proceedings of the National Academy of Sciences of the United States of America, Jun 3, 2024

Impacts of climate change on Australian marine life: part A : executive summary

Influences on the physical marine environment 2.2 Australian marine biomes 2.3 Climate influences... more Influences on the physical marine environment 2.2 Australian marine biomes 2.3 Climate influences on species and communities 2.4 Key non-climate change stessors 3. Australian marine climate change projections 8 4. Vulnerability of marine life to climate change 9 5. Expected impacts on marine life 11 6. Synthesis of main impacts and recommendations 12

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Preliminary mass-balance model of Prince William Sound, Alaska, for the pre-spill period, 1980-1989

A mass-balance model of trophic interactions among the key functional groups of Prince William So... more A mass-balance model of trophic interactions among the key functional groups of Prince William Sound (PWS), Alaska, is presented, based mainly on published data referring to the period from 1980 to 1989, before the Exxon Valdez oil spill. v Research Reports and are distributed to all project or workshop participants. Further copies are available on request for a modest costrecovery charge.

$a) Modified from Degange and Sanger (1986). The original diet fractions for the various birds did not all add up to 1. This was corrected for by modifying the fraction contrib- uted by the most important prey groups. Additional entries not in the table are: mew gulls: 78.19 pammarid amphipods; glaucous- winged gulls: 0.2% hexagrammids, and 0.6% other birds; pigeon guillemot: 1.5% prickle- backs; marbled murrelet: 9.4% mysids. Ce <ul Table 16. Diet matrix for the seabirds of PWS’.$

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The Dynamic Steady State Economy

Frontiers in Ecology and the Environment, Oct 1, 2004

Sufficient fuel taxes would enhance ecologies, economies, and communities

Ecological Economics, Apr 1, 2005

The model presented recently in this journal byBazin et al. (2004) indicates that b...the quality... more The model presented recently in this journal byBazin et al. (2004) indicates that b...the quality of theenvironment can be improved when taxationincreasesQ, as long as the magnitude of the environ-mental tax is sufficient enough so that, b...thefinancial constraints imposed upon the consumerbecome too great and thus limit his desire to consumefurtherQ. In addition, Bosquet’s (2000) survey ofenvironmental tax reform examples indicated thatshifts in tax burdens from socially desirable activities(e.g., employment) to socially undesirable activities(e.g., pollution, resource depletion, and waste) canlead to a ddouble dividendT where both environmentaland economic values are improved. In terms of fueltaxes, the weight of evidence from theory, empiricalstudies, and history indicates their strong potential forsimultaneous enhancement of environmental quality,economic growth, and quality of life, as long as thesetaxes are sufficient and structured appropriately.Bazin et al. (2004) emphasize in their modelingthat the introduction of a small tax or penalty canactually increase the consumptive behaviors of peoplewho perceive the tax to be payment for the right toconsume, pollute, or otherwise degrade public resour-ces. That is to say, the environmental responsibility ofindividual actors can actually decrease with theintroduction of a tax or penalty if the penalty is toosmall. The main empirical example of this compensa-tory bcrowding out effectQ cited by Bazin et al. (2004)was the observation by Gneezy and Rustichini (2000,p. 3) of b...a steady increase in the number of parentscoming lateQ to pick up their children from day-careafter a small late penalty was introduced.It is reasonable to expect that imposing a nominalpenalty would erode parents’ punctuality at a day-carecentre, as these parents might perceive such a fine tobe a price for extracurricular services. We expect nosuch erosion of responsible behavior to occur withrespect to automobile fuel consumption, however,because the consumptive behaviors of typical driversare environmentally irresponsible to start with. UnlikeGneezy and Rustichini’s (2000) tardy parents, typicaldrivers have negligible feelings of responsibilitytowards those adversely affected by their driving(i.e., all people and all life including future gener-ations). If fuel taxes brought prices closer to dfull costpricingT, revenues could be used to defray collateral

Impacts of climate change on Australian marine life

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Membership of the eight Regional Fishery Management Councils in the United States: are special interests over-represented?

Marine Policy, May 1, 2003

The failure of modern fisheries management is blamed on myriad socioeconomic and technical proble... more The failure of modern fisheries management is blamed on myriad socioeconomic and technical problems, but the most fundamental reason for failure might be the overwhelming dominance of extractive interests in participatory decision-making venues. In the United States, commercial fishing interests made up 49% of appointed voting members of the eight Regional Fishery Management Councils between 1990 and 2001; recreational fishing interests made up 33%, and all other interests combined made up 17%. Dominance of commercial fishing representation over the 'other' group was statistically significant, and this unequal apportionment of interests remained statistically stable throughout the 12 years of reporting. Contemporary economic sensibilities within this 'industry-captured' regulatory process generate perverse incentives for management decisions that conflict with, and can undermine, national sustainability goals and standards, even when those standards are logically sound and agreed to by consensus. Positive feedbacks in the system reinforce the unequal representation of interests. The relative dominance of these interests can be adjusted through an experiment that legally mandates an apportionment formula designed to optimize the welfare and interests of the general public, thus testing the notion that increasing the relative representation of general public interests would improve the lacklustre performance of US federal fisheries management.

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Natural disturbances and benthic communities in Monterey Canyon Head

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Effects of climate change on Canada’s Pacific marine ecosystems: a summary of scientific knowledge

Reviews in Fish Biology and Fisheries, Feb 22, 2014

ABSTRACT The marine life of Canada’s Pacific marine ecosystems, adjacent to the province of Briti... more ABSTRACT The marine life of Canada’s Pacific marine ecosystems, adjacent to the province of British Columbia, may be relatively responsive to rapid oceanographic and environmental change associated with global climate change due to uniquely evolved plasticities and resiliencies as well as particular sensitivities and vulnerabilities, given this dynamic and highly textured natural setting. These marine ecosystems feature complex interfaces of coastal geomorphology, climate, and oceanography, including a dynamic oceanographic and ecological transition zone formed by the divergence of the North Pacific Current into the Alaskan coastal current and the California Current, and by currents transporting warm tropical waters from the south. Despite long-term warming in the region, sea surface temperatures in Canada’s Pacific have been anomalously cool since 2007 with La Niña-type conditions prevailing as we enter a cool phase of the Pacific Decadal Oscillation, possibly masking future warming. When warmer El Niño conditions prevail, many southern species invade, strongly impacting local species and reorganizing biological communities. Acidification and deoxygenation are anomalously high in the region due to the weakening ventilation of subsurface waters resulting from increased stratification. A broad spectrum of biological responses to these changes are expected. Non-climate anthropogenic stressors affect the capacity of biota to adapt to climate changes. It will be challenging to forecast the responses of particular species, and to map climate vulnerabilities accurately enough to help prioritize and guide adaptation planning. It will be more challenging to develop forecasts that account for indirect effects within biological communities and the intricate and apparently non-deterministic behaviours of highly complex and variable marine ecosystems, such as those of Canada’s Pacific. We recommend and outline national and regional climate assessments in Canada and adaptation planning and implementation including integrated coastal management and marine spatial planning and management.

Contraction of the banana prawn (Penaeus merguiensis) fishery of Albatross Bay in the Gulf of Carpentaria, Australia

Marine and Freshwater Research, 2008

When the biomass and area occupied by a stock decline together, catch rates can remain high (hype... more When the biomass and area occupied by a stock decline together, catch rates can remain high (hyperstability) and management with effort controls may be ineffectual. Banana prawn (Penaeus merguiensis) catches declined from 2000 until 2005 in the Albatross Bay area in the Gulf of Carpentaria (GOC), Australia. Data from commercial logbooks were used to investigate historical changes in the banana prawn fishery in this and other regions of the Northern Prawn Fishery to infer the potential causes of this decline. Data since 1970 were analysed using: (1) the mapping of catch and effort; and (2) normalised rank order catch curves, to determine the distribution of catches across fishing areas. These analyses show that there has been a marked contraction of the Albatross Bay fishery over 33 years of fishing into the centre of a stable ‘hotspot’, suggesting a potential mechanism for the observed negative relationship between catchability and biomass. We believe this is the first observation of a Peneaus prawn fishing ground contracting as biomass declines, supporting the view that the contraction of an area occupied by a stock as biomass declines, is a generalised phenomena observed widely across fisheries resources and not a dynamic confined to certain finfish and molluscs.

Identifying important species: Linking structure and function in ecological networks

Ecological Modelling, Aug 1, 2008

This article appeared in a journal published by Elsevier. The attached copy is furnished to the a... more This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright Author's personal copy e c o l o g i c a l m o d e l l i n g 2 1 6 (2 0 0 8) 75-80

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Salmon shark connections: North Pacific climate change, indirect fisheries effects, or just variability?

Fish and Fisheries, Dec 1, 2007

Ghoti aims to serve as a forum for stimulating and pertinent ideas. Ghoti publishes succinct comm... more Ghoti aims to serve as a forum for stimulating and pertinent ideas. Ghoti publishes succinct commentary and opinion that addresses important areas in fish and fisheries science. Ghoti contributions will be innovative and have a perspective that may lead to fresh and productive insight of concepts, issues and research agendas. All Ghoti contributions will be selected by the editors and peer reviewed. Etymology of Ghoti George Bernard Shaw (1856-1950), polymath, playwright, Nobel prize winner, and the most prolific letter writer in history, was an advocate of English spelling reform. He was reportedly fond of pointing out its absurdities by proving that 'fish' could be spelt 'ghoti'. That is: 'gh' as in 'rough', 'o' as in 'women' and 'ti' as in palatial.

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Impacts of climate change on Australian marine life: part B : technical report

format_quoteProjected global climate models predict significant warming in the Tasman Sea, severely impacting marine life and ecosystems in southern Australia.format_quote

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Sediment flushing observations, earthquake slumping, and benthic community changes in Monterey Canyon head

Continental Shelf Research, Jul 1, 1997

... Hecker (1982) speculated that submarine landslides destroy existing communities, make new spa... more

Canyon (Usa) Drift Algae: Partitioning Multidimensions

Accumulations of sunken drift macrophytes are known to stimulate high secondary production in sub... more Accumulations of sunken drift macrophytes are known to stimulate high secondary production in submarine canyon heads, but the details of macroinvertebrate colonization of these subsidies are poorly known. I conducted a series of algal and macro- fanual sampling programs and manipulative algal-placement experiments in different Mon- terey Canyon head sub-habitats and seasons from 1988 to 1991 to elucidate the dynamics of macroinvertebrate associations with sunken drift macrophytes, severe annual sediment- flushing events, and the physical and chemical changes associated with these agents of subsidy and disturbance. Conducting these investigations in such a highly disturbed and subsidized setting, i.e., with multiple niche axes, would enable novel insights into how biological communities are structured. Up to 5.7 x 105 individual macrofauna/m2 inhabited naturally occurring patches of sunken drift algae in Monterey Canyon's shallow head (Monterey Bay, California, USA), and the seasonally changing mosaics of macrophyte subsidies led to conspicuously converse responses of amphipods and polychaetes. Amphipods dominated natural patches of sunken algae during winter and spring, while polychaetes dominated during late summer and fall. This community shift corresponded with temporal changes in algal composition, dissolved oxygen (DO), and annual flushing disturbances. Repeated algal-colonization experiments in different habitats further highlighted the contrasting responses of amphipods and poly- chaetes to drift algae and other habitat characteristics. Mean abundances of motile am- phipods increased between 8- and 148-fold within five days after placement of Entero- morpha patches (up to >4 X 105 individuals/m2) while abundances less than doubled in Macrocystis treatments. Amphipod species colonized Enteromorpha treatments in signifi- cantly greater numbers than any controls irrespective of date and sub-habitat. Polychaete species did not colonize algae treatments in significant numbers within five days, but experiments did reveal significant temporal and habitat differences in this group. Sampling of swimming macrobenthos in different canyon habitats and depths (including 30, 100, 300, and 500 m) revealed temporal and habitat patterns in crustaceans and provided explanations of guild functional contrasts. Attributes of two "evolutionary renegades," the phytic polychaete Platynereis bicanaliculata and the hypoxia-tolerant crustacean Nebalia sp., indicated that adaptive constraints inherent in the phenologies and life histories of the two partitioned guilds help reinforce normal functional boundaries. Maximum species rich- ness at intermediate DO and time since disturbance resulted from complementary responses of the two guilds to temporal and habitat characteristics that are shaped by an interacting regime of algal subsidy, hypoxia, and severe flushing disturbance.

Impacts of climate change on Australian marine life: part C : literature review

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Trophic model of the outer continental shelf and upper slope demersal community of the southeastern Brazilian Bight

Scientia Marina, Nov 11, 2011

It is increasingly recognized that demersal communities are important for the functioning of cont... more It is increasingly recognized that demersal communities are important for the functioning of continental shelf and slope ecosystems around the world, including tropical regions. Demersal communities are most prominent in areas of high detritus production and transport, and they link benthic and pelagic biological communities. To understand the structure and role of the demersal community on the southeastern Brazilian Bight, we constructed a trophodynamic model with 37 functional groups to represent the demersal community of the outer continental shelf and upper slope of this area, using the Ecopath with Ecosim 6 (EwE) approach and software. The model indicates high production and biomass of detritus and benthic invertebrates, and strong linkages of these components to demersal and pelagic sub-webs. The level of omnivory indexes in this ecosystem was high, forming a highly connected trophic web reminiscent of tropical land areas. Although high levels of ascendency may indicate resistance and resilience to disturbance, recent and present fisheries trends are probably degrading the biological community and related ecosystem services.

format_quoteThe model reveals that demersal fishes are pivotal for connecting detritus recycling to top predators, key to ecosystem functioning.format_quote

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Factors Affecting Disaster Preparedness, Response, and Recovery Using the Community Capitals Framework

Coastal Management, 2018

Disaster research often focuses on how and why communities are affected by a discrete extreme eve... more Disaster research often focuses on how and why communities are affected by a discrete extreme event. We used the community capitals framework to understand how community characteristics influence their preparedness, response to, and recovery from successive or multiple disasters using the 1964 Good Friday Earthquake and the 1989 Exxon Valdez Oil Spill as case studies. This study assesses community response to these disasters by reviewing published literature on impacts to create profiles for six communities and by identifying community capitals before and during these disasters, and throughout the long-term recovery. While the presence of rich natural capitals commonly contributed resources to pre-disaster planning and long-term recovery, restriction of resource access immediately following the disasters was detrimental to many communities. Communities with strong political, social, and financial capitals tended to fare better immediately following disasters, enabling longer-term processes of transformation or recovery. However, in some communities the oil spill undermined these capitals more than the earthquake and resulting tsunami. In understanding how use and reliance on community capitals can lead to varied recovery success from different kinds of disasters, these findings can help coastal managers and planners prepare for future disasters.

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for the Pre-Spill Period, 1980-1989

with editorial contributions by

Brief of Amicus Curiae filed in support of respondents in U.S. Supreme Court Case No. 07-219: Exxon Shipping Co., and Exxon Mobil Corp. (Petitioners) v. Grant Baker, et al. (Respondents)

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