Mackenzie Mazur

Fisheries and Oceans Canada | DFO

Individual-based models (IBMs) can capture complex processes with a flexible probabilistic approach, which makes them useful for studying organisms with complex life history and fishery processes such as the American lobster (Homarus americanus). This research aims to modify and parameterize an individual-based lobster simulator (IBLS) to simulate th...

V-notching, a conservation measure intended for the protection of mature female lobsters, has been hypothesized to have contributed to the dramatic increase in American lobster Homarus americanus landings and stock biomass in the Gulf of Maine. To evaluate the impact of this conservation measure, scenarios examining different v-notching compliance...

American lobster (Homarus americanus) supports one of the most valuable regional fisheries in the United States, with its abundance and distribution profoundly influenced by environmental conditions. To explain how lobster distribution has changed over time and assess the role of environmental variables on these changes, we used random forest class...

Understanding compliance is important for understanding the effectiveness of conservation. This study examines conservation compliance in the American lobster fishery in Maine. In this fishery, an important conservation measure that protects spawning female lobsters, known as v-notching, is considered a norm. This conservation rule is primarily sel...

Functional stock-recruitment relationships (SRRs) are often difficult to quantify and can differ over space. Additionally, climate change adds to the complexity of recruitment dynamics. This paper's aim was to incorporate spatial heterogeneity and environmental effects on productivity in SRRs with American lobster in the Gulf of Maine (GOM) as a ca...

Climate change is fueling unprecedented warming in marine environments. Crustaceans demonstrate strong physiological responses to rising temperatures including smaller molt increments, more frequent molting, and decreased size-at-maturity (SAM). Despite the potential for these changes to affect population and fisheries dynamics, there is limited re...

Crustacean species are socioeconomically and ecologically crucial across the world. For crustaceans, as ectotherms, anthropogenic climate change threatens to significantly alter key life history characteristics, such as size at maturity and growth rate. Because crustaceans are difficult to age, length data are used in assessments of crustacean stoc...

China’s coastal areas face serious environmental degradation as a consequence of large-scale economic development. To balance environmental sustainability with economic development, China is currently implementing a strategy of ‘eco-civilization’, with marine protected areas (MPAs) expected to be one approach to achieving sustainable marine ecosyst...

Ethics are becoming a component of best practices in ocean science and observing systems, with the research community facing a duty to society to maximize the efficient use and benefits that stem from investments in ocean science/monitoring. Sustained ocean observing systems on issues of global importance are coordinated, internationally sanctioned...

Climate change is continuing to influence spatial shifts of many marine species by causing changes to their respective habitats. Habitat suitability as a function of changing environmental parameters is a common method of mapping these changes in habitat over time. The types of models used for this process (e.g. bioclimate models) can be used for p...

Different approaches have been used to identify fishery stock status when only biomass and catch data are available. However, the performance of the approaches may be affected by the uncertainties derived from different sources (e.g., model misspecification, stock productivity changing, observation error). Here, we propose that the observed biomass...

This workshop is the third in a series of workshops on guidelines for developing Management Strategy Evaluations (MSEs) within ICES, and was intended to explore some of the issues that arose out of workshops that actually developed MSEs for a range of ICES stocks since the second MSE guidelines workshop was held in early 2019. It is intended that r...

Reef fish are highly valuable to human society—socially, nutritionally and economically. However, they are vulnerable to both overfishing and habitat degradation. Understanding the community structure and habitat associations of reef fish is important for their management and conservation. Using a gillnet survey conducted in a subtropical rocky ree...

Outliers caused by atypical observation error often occur in fishery data. These outliers have an adverse effect on the parameter estimation for fishery stock assessment models. We tested a robust distribution for identifying and removing outliers from fishery data. We conducted a simulation study in which a surplus production model was used to mim...

Understanding both the social and biological factors surrounding conservation is important for informing effective fisheries management. This dissertation examines conservation in the American lobster (Homarus americanus) fishery in a changing Gulf of Maine (GOM) using computer simulations informed by interviews with lobster fishers. In this fisher...

Changes in bottom-up forcing are fundamental drivers of fish population dynamics. Recent literature has highlighted the need to incorporate the role of dynamic environmental conditions in stock assessments as a key step towards adaptive fishery management. Combining a bioclimate envelope model and a population dynamic model, we propose a model-base...

The American lobster, Homarus americanus H. Milne-Edwards, 1837, fishery is the most valuable commercial fishery in the state of Maine (United States), and contributes more than US$666 million to the global market. Although lobster landings are at a historically high level, scientists have identified a myriad of threats that raise concern about the...

Estimating spatial distribution of a species is traditionally achieved using global regression models with the assumption of spatial stationarity of relationships between species and environmental variables. However, species abundance and environmental variables are often spatially correlated and the strength of environmental effects may exhibit sp...

Increasing amounts of paralytic shellfish toxins (PSTs) threaten human health, the economy, and marine ecosystems because of paralytic shellfish poisoning (PSP). Therefore, studies about shellfish toxicity can have significant public health and social impact. In this study, the effect of water temperature on PST uptake in blue mussels (Mytilus edul...