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The inshore commercial fishery for American Lobster (Homarus americanus) has been active for over 150 years in Lobster Fishing Areas (LFAs) 34-38. These areas cumulatively cover 34,000 km² from southwestern Nova Scotia, north to the Bay of Fundy and along the New Brunswick coast to the Canadian--United States border. The fishery is active throughout the LFAs with both inshore and offshore components. Lobster stocks in LFAs 34-38 have a long history of assessments which are conducted almost annually. The last framework for assessing Lobster in LFAs 34-38 occurred in 2013 with separate assessment documents for LFA 34 and LFAs 35-38. The most recent stock assessments for LFA 34 use landings, the Inshore Lobster Trawl Survey (ILTS) catch rate index, and raw commercial catch rates as primary indicators of stock status. LFAs 35-38 were assessed as one unit with a single set of primary stock status indicators. These indicators include landings, raw commercial catch rates, and total abundance from the Fisheries and Oceans Canada (DFO) summer Research Vessel (RV) survey. In this stock assessment framework the stock status indicators were re-examined and their methodologies for estimation evaluated. Background on the available data sources and analyses were described. The code to perform all analyses is available on a GitHub repository. This framework will provide information on ecological and environmental indicators, incrementally moving toward applying an ecosystem approach to stock assessments. Indicators will be estimated for each LFA separately. It was recognized that there are likely connections between LFAs and similar processes impacting production; however, each LFA is managed separately with unique conservation measures adopted. There are three groups of indicators in this document, primary, secondary, and contextual. The primary indicators will be used to define stock status, and reference points will be developed. Secondary indicators are those in which time-series trends will be updated and displayed in subsequent stock status reports; however, no reference points will be developed for these indicators. The contextual indicators will be included in stock assessments, and will be infrequently updated. The data used in this stock assessment represent a mixture of both fisheries dependent and fisheries independent data. The fisheries independent data come from a number of mobile sampling methods. Each of these surveys cover a portion of the overall stock area. The longest time series of data on the Lobster within these LFAs comes from the fisheries dependent data. [ABSTRACT FROM AUTHOR]

The Lobster Fishing Area (LFA) 41 offshore Lobster fishery has been active since the early 1970s and is currently the only Total Allowable Catch (TAC) based Lobster fishery in Canada. The TAC has been set to 720 t since the mid-1980s without change, despite increases in survey biomasses. The fishery currently has 8 licenses, which are owned by a single corporation and are fished from a single vessel. This stock assessment framework updates that of Pezzack et al. 2015 by exploring the impact of stock boundaries on indicator trends as well as expanding the suite of indicators used to describe the ecosystem and Lobster stock and exploring options for defining stock status and reference points. Four multispecies trawl surveys conducted by two agencies, Fisheries and Oceans Canada (DFO) and the National Marine Fisheries Service (NMFS), occur within LFA 41 and adjacent areas. Each of these surveys provides indices of biomass and abundance, size frequency, sex ratio, distribution and environmental variables. Six at-sea observed trips are conducted each year, which provides further information on by-catch profiles and Lobster size and sex information. Time series' of a suite of standard indicators including total abundance, median and maximum size, mature and immature sex ratio, patchiness of distribution, area occupied, abundance of large females and recruit abundance were used to describe the changes in the LFA 41 Lobster stock over time. Additionally, ecosystem indices including predation, bottom water temperature, the Atlantic multidecadal oscillation (AMO) were provided to describe some of the external factors which may impact Lobster productivity. All indicators were combined and ranked through a modified principle components analysis to display the coherence in indicator trends over time. Overall, patterns suggest decreasing median and maximum size of the Lobster stock over time, as well as decreasing predation pressure and increasing abundance, distribution, bottom temperature and AMO. The LFA 41 stock has never been assessed with a quantitative stock assessment model. Here, a biomass-dynamic model fit through Bayesian state-space methods was attempted for this stock. The carrying capacity parameter was not well defined and was influenced by the median of the prior distribution. The inability to define parameters was partially due to the lack of contrast in the data from the constant TAC despite increased survey biomasses. It was concluded that this quantitative model was currently inappropriate to provide estimates of stock status and reference points, but should be explored in future. Data driven primary indicators and methods to develop upper stock and limit reference indicators (USI and LRI, respectively) were described. Several options for reference indicators were explored for each of the four surveys covering LFA 41, with the recommendation of a USI being based on survey biomasses from the high productivity period and a LRI defined similar to Brecover. Although each of the surveys had very similar trends in commercial biomass, with recent years being the highest on record, the recommendation was to continue using all four surveys and evaluate the overall stock status based on the status of 3 of the 4 survey trends. Specifically, 3 of 4 survey trends would need to be below their respective USI's in order for the stock to be considered in the cautious zone. Similarly, 3 of 4 survey trends would need to be below their respective LRI's in order for the stock to be considered in the critical zone Methods to describe removal references were described; however, due to the stable TAC and currently increasing biomass, the impact of harvesting on stock status was not readily determined. The recommendation was to not provide a removal reference based on the information currently available. A reproductive potential primary indicator was developed along with boundaries relating to stock productivity. Reproductive potential has long been considered an important component of Lobster stock productivity that is in need of protection, and although this may be more important for inshore Lobster fisheries that are largely recruitment fisheries, the LFA 41 Lobster stock is predominated by large female Lobsters. Removal references and stock status zones were not defined for the reproductive potential indicator; however, it was recommended to be tracked independent of the other indicators as changes may be indicative of the state of future stock productivity. Analysis of bycatch data and research recommendations were also included in this framework document. [ABSTRACT FROM AUTHOR]