Inland fisheries - invisible but integral to the UN Sustainable Development Agenda for ending poverty by 2030

In PressJournal Article
Lynch AJ, Cowx IG, Fluet-Chouinard E, Glaser SM, Phang SC, Beard TD Jr., Bower SD, Brooks JL, Bunnell DB, Claussen JE, Cooke SJ, Kao YC, Lorenzen K, Myers BJE, Reid AJ, Taylor JJ, Youn S.
Global Environmental Change. 47:167–173

Abstract

The Sustainable Development Goals (SDGs; promulgated in 2015), officially known as “Transforming our world: the 2030 Agenda for Sustainable Development”, are an intergovernmental set of 17 goals and 169 constituent targets that succeed the Millennium Development Goals (MDGs; 2000–2015). Despite a clear mandate to integrate social, economic and environmental objectives in the SDGs, ecosystem health remains underrepresented in this latest iteration of the United Nation’s global development agenda. We submit that maintaining ecosystem health (Goal 14: life below water and Goal 15: life on land) is a necessary precondition to achieving the 2030 Agenda for Sustainable Development. Here, we present a reconceptualized SDG framework akin to a tree that places Healthy Ecosystems as the roots for five branches of development (Clean Energy, Water Security, Food Security, Lives and Livelihoods, Governing for Sustainability). As universal examples, we put forward the vital role of life below fresh water for ending poverty by 2030 (Goal 1: no poverty) and describe how children’s environmental health is the foundation for the major health priorities of reproductive, maternal and child health (Goal 3: good health and well-being). This framework provides insight and evidence for policymakers and the public to be cognizant that prioritizing ecosystem health goals can serve human development objectives which we deem as key to realizing the unified plan of action for people, planet and prosperity.

Post-2015 sustainable development goals still neglecting their environmental roots in the Anthropocene

Journal Article
Reid AJ, Brooks JL, Dolgova L, Laurich B, Sullivan BG, Szekeres P, Wood SL, Bennett JR, Cooke SJ.
Environmental Science and Policy. 77:179-184.

Abstract

The Sustainable Development Goals (SDGs; promulgated in 2015), officially known as “Transforming our world: the 2030 Agenda for Sustainable Development”, are an intergovernmental set of 17 goals and 169 constituent targets that succeed the Millennium Development Goals (MDGs; 2000–2015). Despite a clear mandate to integrate social, economic and environmental objectives in the SDGs, ecosystem health remains underrepresented in this latest iteration of the United Nation’s global development agenda. We submit that maintaining ecosystem health (Goal 14: life below water and Goal 15: life on land) is a necessary precondition to achieving the 2030 Agenda for Sustainable Development. Here, we present a reconceptualized SDG framework akin to a tree that places Healthy Ecosystems as the roots for five branches of development (Clean Energy, Water Security, Food Security, Lives and Livelihoods, Governing for Sustainability). As universal examples, we put forward the vital role of life below fresh water for ending poverty by 2030 (Goal 1: no poverty) and describe how children’s environmental health is the foundation for the major health priorities of reproductive, maternal and child health (Goal 3: good health and well-being). This framework provides insight and evidence for policymakers and the public to be cognizant that prioritizing ecosystem health goals can serve human development objectives which we deem as key to realizing the unified plan of action for people, planet and prosperity.

Oxford Bibliography: Aquatic Conservation

Online Reference
Brownscombe JW, Reid AJ, Dolgova D, Pusiak R, Laurich B, Turenne ED, Zolderdo A, Moraga A, Birnie-Gauvin K, Brooks J, Sullivan B, Ford M, Bower SD, Bennett JR, Cooke SJ.
Oxford Bibliographies, Oxford University Press.

Abstract

Conservation biology—a “crisis-discipline” focused on protecting and restoring the earth’s biological diversity—has focused historically on terrestrial ecosystems and threats. This may be expected given that humans are a land-based species whose impact is superficially more evident on land than below the water’s surface. However, there is a pronounced need for knowledge of the status of aquatic ecosystems (i.e., marine, brackish, and freshwater) as they cover nearly three-quarters of the planet’s surface and account for 90 percent of its inhabitable volume. Alarmingly, aquatic ecosystems face mounting threats from humanity’s unabated use and unmanaged inputs. Aquatic conservation, as the name implies, is a subdiscipline of scholarly research and practice that is focused on applying conservation knowledge to address the growing challenges faced by aquatic ecosystems which include freshwater, brackish, and marine waters. While fundamentally rooted in aquatic ecology, aquatic conservation draws from other related natural sciences (e.g., genetics, physiology, evolutionary biology, oceanography, limnology) and social sciences (e.g., economics, political science, sociology, legal studies), making it a truly integrative approach to assessing, protecting, managing, and restoring aquatic ecosystems and species.

Review and evaluation of fishing-related incidental mortality for Pacific salmon

Scientific Report
Patterson DA, Robinson KA, Lennox RJ, Nettles TL, Donaldson LA, Eliason EJ, Raby GD, Chapman JM, Cook KV, Donaldson MR, Bass AL, Drenner SM, Reid AJ, Cooke SJ, Hinch SG. 2017. Review and evaluation of fishing-related incidental mortality for Pacific salmon
Fisheries and Oceans Canada Canadian Science Advisory Secretariat. 155 p.

Abstract

The number of fish that encounter fishing gear is greater than the number of fish retained as catch. The proportion of this difference that die from the encounter is defined as fishing-related incidental mortality (FRIM). FRIM estimates are required for improved stock assessments, but they are difficult to attain and vary across fisheries. To cope with this challenge we review and evaluate the scientific knowledge on FRIM. First, we review the different mortality components of FRIM (i.e., avoidance, escape, depredation, drop-out, on-board, short-term release, and delayed mortality) in relation to how a fish responds to different aspects of a fishery encounter (e.g., handling). To better understand how fish respond to a fishing encounter, different fishing factors (e.g., gear type) that act in consort with extrinsic (e.g., water temperature) and intrinsic (e.g., fish size) factors elicit different fish responses that can lead to the different types of mortality (e.g., acute) were examined. A fish response to a stressor (i.e., factor) is a combination of the magnitude and duration of the stressor itself. The initial fish response includes acute physiological stress and injury, followed by behaviour changes, chronic stress, and increased risk of infection. Next, a review was done to provide an up-to-date accounting of the mortality rate information available on estimates of FRIM for Pacific salmon (Oncorhynchus spp.). We created an interactive and searchable catalogue of evidence from predominantly primary literature using standardized systematic mapping protocols, with a focus on coding information to determine study reliability and relevance. Next, we synthesize the factor and mortality information to provide recommendations on the use of five major mortality risk factors that are linked to FRIM. Each factor (capture, handling, injury, water temperature, and predators) is scaled to a mortality risk to provide guidance on evaluating FRIM estimates. The recommendations from this work are focussed on addressing the current knowledge gaps and examining FRIM in broader physiological and ecological context. Ideas for future work include researching cumulative impacts, sub-lethal effects, drop-off mortality, and predation. We have chosen a fish-centric hybrid approach that focusses first on understanding factors that drive mortality, and then on mortality estimates. As such, this paper is not meant as the definitive guide on FRIM but a transparent, defensible, and rigorous evaluation of the primary evidence base for making future decisions about FRIM. Further guidance on how to use the information herein is part of an accompanying CSAS research document.

Implications of hypoxia tolerance for wetland refugia use in Lake Nabugabo, Uganda

Journal Article
Reid AJ, Farrell MJ, Luke MN, Chapman LJ.
Ecology of Freshwater Fish. 22:421-429.

Abstract

Aquatic hypoxia can affect predator-prey interactions by altering the success rate of the predator and/or the vulnerability of prey. For example, in the Lake Victoria basin of East Africa, native prey exploit hypoxic wetlands as refugia from predation by introduced Nile perch (Lates niloticus). Here, it is predicted that species exploitation of wetlands depends on their hypoxia tolerance relative to the heterogeneity of wetland hypoxia. In this study, we compared the hypoxia tolerance of four fish taxa that differ in their use of hypoxic wetlands in Lake Nabugabo, Uganda: the cichlid Pseudocrenilabrus multicolor victoriae that inhabits the dense swamp interior; and three taxa that inhabit wetland ecotones including Nile tilapia (Oreochromis niloticus), L. niloticus and juvenile endemic haplochromine cichlids. We characterised hypoxia tolerance by exposing fish to progressive hypoxia and quantifying variation in aquatic surface respiration (ASR). The effect of body size on tolerance was explored in L. niloticus by quantifying ASR behaviour across a range of size classes. ASR behaviour was also compared between O. niloticus groups from wetland versus open-water habitats to detect habitat-associated intraspecific variation. The most tolerant taxon was the swamp specialist P. multicolor, indicated by its low ASR thresholds and small percentage of fish using ASR during the final sample interval. The other three taxa did not differ in ASR behaviour, and no differences were detected between O. niloticus groups. Body size effects were present for L. niloticus suggesting a lower tolerance to hypoxia in larger-bodied individuals, thus limiting their ability to penetrate wetlands.

Wetland edges as peak refugia from an introduced piscivore

Journal Article
Reid AJ, Chapman LJ, Ricciardi A.
Aquatic Conservation: Marine & Freshwater Ecosystems. 23:646-655.

Abstract

1. Wetlands in the Lake Victoria basin serve as structural and hypoxic refugia for some native fishes against predation by introduced Nile perch (Lates niloticus); however, little is known about the fine-scale patterns of distribution and abundance of these refuge inhabitants.

2. This study sought to quantify wetland ecological gradients and determine where peaks in native fish abundance and richness (‘peak refugia’) occurred using Lake Nabugabo, Uganda as a model system.

3. Extensive wetland transects were sampled between June and August, 2011 to measure ecological variation over distance from the lake–wetland edge.

4. Wetlands were characterized by strong clines in water temperature, pH, dissolved oxygen (DO), depth and vegetation density, and narrow peak refugia were found precisely at the lake–wetland edge. Community richness and diversity tended to be greater in areas with higher DO and lower temperature, pH, and vegetation density. It is interesting that areas encroached upon by a native emergent macrophyte (hippo grass, Vossia cuspidata) had more extreme physico-chemical conditions and supported fewer native fish species.

5. These results demonstrate the importance of wetland edges in the maintenance of native fish fauna in the Lake Victoria basin, and suggest that the continued expansion of hippo grass may reduce the accessibility of wetlands as refugia.

6. We recommend that the use of spatially explicit management approaches such as the development of secure buffer zones surrounding wetland edges to protect peak refugia, and the need for hippo grass control to minimize its effects on this important refuge.

Predicting peak refugia for mitigating impacts of invasive predatory fishes

Thesis
Reid, AJ.
McGill University. 91 p.

Abstract

Areas outside the distributional boundaries of an introduced predator may be exploited by native prey as refugia from predation. A classic example is the Lake Victoria basin of East Africa where hypoxic (low oxygen) wetlands serve as refugia for some native fishes from introduced Nile perch (Lates niloticus). In this thesis I quantified patterns of wetland refugia use in Lake Nabugabo, Uganda, a satellite of Lake Victoria, to achieve two primary goals: (i) identify peak refugia, where the greatest abundance and richness of native fishes persist, and (ii) directly link hypoxia tolerance of native and introduced fishes to their wetland distributions. A field survey indicated that peak refugia occur at the lake-wetland edge, and that strong edge-related gradients are shaping the fish assemblage structure of wetland habitats. Species richness and diversity were positively related to dissolved oxygen availability, and negatively related to temperature, pH, and vegetation density. Experiments quantifying the behavioural response of fish to progressive hypoxia revealed the highest tolerance to hypoxia in the swamp specialist Pseudocrenilabrus multicolor, when compared with three taxa found at the lake-wetland edge: juvenile endemic haplochromine cichlids, Nile tilapia (Oreochromis niloticus), and Nile perch. Tolerance to hypoxia decreased with increased body size in Nile perch, which may limit penetration of the wetland edge in larger-bodied Nile perch. By establishing a link between physico-chemical gradients and peak refugia our study points to the importance of invader-edge dynamics in determining the outcome of interactions between introduced predators and resident prey.

Macronutrient balancing affects patch departure by guerezas (Colobus guereza)

Journal Article
Johnson CA, Raubenheimer D, Chapman CA, Tombak KJ, Reid AJ, Rothman JM.
American Journal of Primatology. 79:1-9.

Abstract

Foraging strategies are central in shaping social structure and grouping patterns in primates. We address Colobus guereza foraging strategies by investigating their patch departure decisions in relation to diet composition and nutrition. We examine whether guerezas are constrained in their intake of food in patches and thereby forage according to a fixed amount strategy that dictates patch departure. Additionally, we assess whether guereza employ a fixed time strategy or attempt to balance nutrients when foraging. We measured food patch occupancy time, intake rates, and analyzed foods for macronutrients, fiber, and condensed tannins. We determined that guerezas do not employ a fixed time foraging strategy; patch residence time varied widely between 1 and 290 min. They also did not depart patches or stop eating when they reached a specific intake of dry mass, macronutrients, or condensed tannins. However, guerezas maintained a macronutrient balance when feeding across patches, and the balance of protein to non-protein energy (fats and carbohydrates) in patches is the best indicator of time adult guerezas spent feeding in patches. Previous studies have shown that the protein-to-fiber ratio is important in predicting food selection for folivores and their biomass; however, we found that guerezas did not maximize protein and minimize fiber intake while foraging in patches, nor did they stay longer in patches with the highest ratio of protein to fiber concentrations. This study raises questions about the nutritional and social implications of patch depletion as a foraging strategy in folivorous monkeys where food limitation predicts competitive and social regimes.

Patch depletion behavior differs between sympatric folivorous primates

Journal ArticleThesis
Johnson CA, Raubenheimer D, Chapman CA, Tombak KJ, Reid AJ, Rothman JM.
Primates. 53:57-64. *Equal contributors

Abstract

Food competition in group-living animals is commonly accepted as a critical determinant of foraging strategies and social organization. Here we examine food patch depletion behavior in a leaf-eating (folivorous) primate, the guereza (Colobus guereza). Snaith and Chapman (2005) studied the sympatric folivorous red colobus (Procolobus rufomitratus), which shares many food resources with the guereza. They determined that red colobus deplete the patches (feeding trees) they use, while we found contrary evidence for guerezas using the same methods. We found that the time guerezas spent feeding in a patch was affected by neither tree size, an indicator of food abundance, nor the size of the feeding group, an indicator of feeding competition. For their principal food item (young leaves), intake rate remained constant and coincided with a decrease in the distance moved to find food within a patch, implying that guerezas do not deplete patches. This points to a fundamental difference in the use of food by guerezas and red colobus, which may be linked to the large difference in their group sizes and/or to a disparity in their digestive physiologies. However, further analyses revealed that the number of feeders within a patch did not affect patch depletion patterns in either species, leaving the potential for a physiological basis as the most plausible explanation. Our research highlights the need for a more critical examination of folivorous primate feeding ecology and social behavior, as all folivorous primates are typically lumped into a single category in socioecological models, which may account for conflicting evidence in the literature.