The impact of predation by marine mammals on Patagonian toothfish longline fisheries

Predatory interaction of marine mammals with longline fisheries is observed globally, leading to partial or complete loss of the catch and in some parts of the world to considerable financial loss. Depredation can also create additional unrecorded fishing mortality of a stock and has the potential to introduce bias to stock assessments. Here we aim to characterise depredation in the Patagonian toothfish (Dissostichus eleginoides) fishery around South Georgia focusing on the spatio-temporal component of these interactions. Antarctic fur seals (Arctocephalus gazella), sperm whales (Physeter macrocephalus), and orcas (Orcinus orca) frequently feed on fish hooked on longlines around South Georgia. A third of longlines encounter sperm whales, but loss of catch due to sperm whales is insignificant when compared to that due to orcas, which interact with only 5% of longlines but can take more than half of the catch in some cases. Orca depredation around South Georgia is spatially limited and focused in areas of putative migration routes, and the impact is compounded as a result of the fishery also concentrating in those areas at those times. Understanding the seasonal behaviour of orcas and the spatial and temporal distribution of “depredation hot spots” can reduce marine mammal interactions, will improve assessment and management of the stock and contribute to increased operational efficiency of the fishery. Such information is valuable in the effort to resolve the human-mammal conflict for resources

Dynastid white grubs as rainfed rice pests of agrosystem engineers in Madagascar [Poster].

International audienc

The importance of future generations and conflict management in conservation

The need to scale-up conservation initiatives is widely accepted, but understanding how to catalyze the adoption of conservation initiatives remains elusive. To address this challenge, we used diffusion of innovation theory and Best-Worst Scaling experiments to rank the factors that influence the adoption of Locally Managed Marine Areas (LMMAs) by villages in north Madagascar. The most important driver for respondents to adopt LMMAs was the wellbeing of future generations, while the most important barrier was conflict within and between villages that could arise from the adoption of LMMAs. This emphasis on the benefits and costs of adoption is consistent with diffusion of innovation theory. However, our results indicate that people's intrinsic values (e.g., benevolence and peace) were more important to survey respondents in the adoption of LMMAs than is generally reported in the diffusion of innovation literature. Concerns about conflict from LMMAs and the distribution of livestock incentives warrant further consideration to support the adoption of this conservation initiative in the context of the Sustainable Development Goals. Our study can guide future conservation research and practice to identify the “best” and “worst” attributes of LMMAs and other initiatives to increase the adoption of conservation

Les vers blancs du riz pluvial d'altitude (Col. Scarabaeoidea) à Madagascar : effets de la plante-hôte et de la matière organique du sol sur le comportement larvaire

Sur les Hauts-Plateaux malgaches, les vers blancs (Coleoptera : Scarabaeoidea), représentés par de nombreuses espèces, sont considérés comme des ravageurs majeurs du riz pluvial. Toutefois, cette perception est partiellement erronée, la relation de ces insectes à la culture variant selon les espèces et le statut organique du sol. En microcosmes au laboratoire, les larves du Cetoniidae Bricoptis variolosa et du Dynastidae Hexodon unicolor unicolor ont présenté un régime saprophage strict, ne causant jamais aucun dommage à la culture. Celles du Melolonthidae Apycencya sp. nov. se sont montrées strictement rhizophages, et celles des Dynastidae Heteronychus spp (H. plebejus, H. bituberculatus et H. arator rugifrons) et Heteroconus paradoxus rhizophages facultatives, ne s'attaquant aux racines de riz qu'en sols pauvres en matière organique. Chez H. arator rugifrons et H. paradoxus, un effet phagostimulant du fumier de bovin a été mis en évidence, se traduisant par un gain de poids des larves significativement plus élevé dans du sol additionné de paille de riz, en présence de sacs de toile remplis de fumier vs de sol seul ou de sol imprégné d'humus liquide. Ces résultats ouvrent de nouvelles perspectives de gestion des vers blancs, particulièrement avec les systèmes en semis direct sur couverture végétale (SCV). (Résumé d'auteur

Data and code for LMMA adoption in Madagascar 2018 Lewis-Brown et al

In 2018 questionnaires were undertaken in four villages in NE Madagascar to assess the drivers and barriers to adoption of Locally Managed Marine Areas (LMMAs) through a Best-Worst Scaling (BWS) choice experiment. The data and code are deposited to accompany a journal article to be published in Conservation Science and Practice in 2021.

Multiscale determinants of social adaptive capacity in small-scale fishing communities

Climate change is expected to reinforce undesirable social and ecological feedbacks between ecosystem degradation and poverty. This is particularly true for resource-dependent communities in the developing world such as coral reef fishing communities who will have to adapt to those new environmental conditions and novel ecosystems. It is therefore crucial to identify: i) multiscale characteristics that can influence social adaptive capacity of local communities to climate change, and ii) current and future social-ecological conditions related to climate change that might lead communities to experience unsustainable and undesirable states (i.e., "socialecological traps"). Here, we investigated social adaptive capacity and the relationship to ecological conditions in 29 small-scale fishing communities in Madagascar and Kenya in the Western Indian Ocean. We found that isolation from a market and climate stress had a significant negative relationship with social adaptive capacity, while a higher level of education and the presence of market traders (middlemen) had a positive relationship. In general, resource management through marine protected areas and locally managed marine areas had a positive influence on ecological conditions. Combining social adaptive capacity and ecological conditions revealed that 80 % of fishers households surveyed were experiencing social-ecological states that could lead to unsustainable social-ecological conditions, while 10 % might already be experiencing social-ecological traps. Our findings reveal specific mechanisms by which conservation and development activities can increase social adaptive capacity in coastal communities, including but not limited to: increasing market access and education, and mitigating future climate exposure and unsustainable fishing through improved marine conservation and management

Transitions towards co-management: the process of marine resource management devolution in three east African countries

Communities are increasingly empowered with the ability and responsibility of working with national governments to make decisions about marine resources in decentralized co-management arrangements. This transition toward decentralized management represents a changing governance landscape. This paper explores the transition to decentralisation in marine resource management systems in three East African countries. The paper draws upon expert opinion and literature from both political science and linked social-ecological systems fields to guide exploration of five key governance transition concepts in each country: (1) drivers of change; (2) institutional arrangments; (3 institutional fit; (4) actor interactions; and (5) adaptive management. Key findings are that decentralized management in the region was largely donor-driven and only partly tranferred power to local stakeholders. However, increased accountability created a degree of democracy in regards to natural resource governance that was not previously present. Additionally, increased local-level adaptive management has emerged in most systems and, to date, this experimental management has helped to change resource user's views from metaphysical to more scientific cause-and-effect attribution of changes to resource conditions

Comanagement of coral reef social-ecological systems

In an effort to deliver better outcomes for people and the ecosystems they depend on, many governments and civil society groups are engaging natural resource users in collaborative management arrangements (frequently called comanagement). However, there are few empirical studies demonstrating the social and institutional conditions conducive to successful comanagement outcomes, especially in small-scale fisheries. Here, we evaluate 42 comanagement arrangements across five countries and show that: (i) comanagement is largely successful at meeting social and ecological goals; (ii) comanagement tends to benefit wealthier resource users; (iii) resource overexploitation is most strongly influenced by market access and users’ dependence on resources; and (iv) institutional characteristics strongly influence livelihood and compliance outcomes, yet have little effect on ecological conditions