Northern wolffish and spotted wolffish recovery strategy: chapter 11


Recovery

1. Overview

This document is the first component of a framework to promote the conservation and recovery of three wolffish species in eastern Canadian waters. The second component, the Action Plan (as outlined in Part B, Section 7) will be completed at a later date. Where an activity has already been initiated to address the objectives laid out in this document, these actions are duly noted in Part B, Section 5 - Actions Completed or Underway.

The Recovery Team determined that it was best to incorporate both threatened wolffish species into a single “multi-species” document and to include A. lupus, a species of special concern, in the discussions due to their similar life histories, ecology and taxonomically close relationship. As such, this document represents both a recovery strategy for A. denticulatus and A. minor, as well as a management plan for A. lupus. As SARA prohibitions are not applicable to special concern species, conservation and recovery activities described in this document should be viewed as recommendations only for A. lupus.

2. Goals, Objectives And Strategies

2.1 The Recovery and Management Goal

The goal of this Recovery Strategy and Management Plan is to increase the population levels and distribution of A. denticulatus, A. minor and A. lupus in eastern Canadian waters such that the long-term viability of these species is achieved. This will be accomplished by communicating those objectives and strategies outlined below.

2.2 Recovery and Management Objectives

The Recovery Strategy and Management Plan for wolffish species in eastern Canadian waters puts forth five broad inter-related objectives. All relate to activities that may be mitigated through human intervention.

Objective 1: Enhance knowledge of the biology and life history of wolffish species;

Objective 2: Identify, conserve and/or protect wolffish habitat required for viable population sizes and densities;

Objective 3: Reduce the potential of wolffish population declines by mitigating human impacts;

Objective 4: Promote wolffish population growth and recovery; and

Objective 5: Develop communication and education programs to promote the conservation and recovery of wolffish populations.

Each of these broad objectives is designed to achieve the goals of this document. As this Recovery Strategy and Management Plan is considered to be adaptive (i.e. a living document), objectives and strategies can be added or revised as new knowledge becomes available.

The following sections elaborate on the above objectives and link them with recovery strategies that include specific actions required for implementing this document. The order in which the strategies are presented does not reflect a ranking of importance. Rather, all strategies are considered critical to the recovery process and are recommended to be carried out in an integrated manner. The consequent activities (actions) of the recovery action plan will result in the implementation of the recovery strategies and objectives.

In general, the recovery of a species at risk involves a multi-faceted approach that takes into consideration individual populations, the number and nexus of these populations and the creation of adequate population levels to withstand events such as environmental shifts and climate change. According to the National Recovery Working Group, establishing a sustainable population requires:

  • enough breeding adults to be considered sustainable in the long term;
  • sufficient quality habitat available or potentially available to maintain sustainable population numbers;
  • adequate or improving demographic parameters (e.g., sex ratio, birth and death rates); and
  • mitigation against and control of human threats to the population, particularly those that initially contributed to the species’ decline.

2.3 Recovery Strategies and Specific Actions to Meet Recovery Objectives for Wolffish Species

Five strategies constitute the basis of a framework for recovery: research, habitat conservation and protection, mitigation of human activities, promotion public knowledge and stakeholder participation in the recovery of wolffish populations and the conservation and protection of their habitat and monitoring of human activities. Associated specific actions required to achieve species recovery and anticipated effects of those actions are listed in Table 21.

Table 21. Linking recovery objectives to strategies and specific actions required to promote recovery of wolffish species
Priority Recovery Objective Recovery Strategy Recovery Actions Anticipated Effect
Necessary, on going 1, 2, 4 A. Research

Conduct directed research on:

1. life history

2. population structure

3. identify limit reference points

4. ecosystem interactions

Better adaptive management decisions

Necessary,

On going

2, 4, 5 B. Habitat conservation and protection

1. identify habitat

2. define measures to conserve and/or protect wolffish habitat

Increase potential of spawning, rearing, feeding, and other life processes
Urgent 3, 4, 5 C. Mitigate human activities 1. identify and mitigate impacts Direct benefit to species numbers, reducing mortality at all life stages

Necessary,

On going

3, 4, 5 D. Promote public knowledge and stakeholder participation in the recovery of wolffish populations and the conservation and protection of their habitat

Through:

1. education

2. stewardship

3. consultation

4. cooperation

Support for management measures and other recovery strategies
On going 3, 4 E. Monitor human activities

1. monitor wolffish spatial and temporal abundance patterns

2. monitor spatial and temporal patterns in natural and human induced mortality

Better adaptive management decisions

2.4 Recovery Strategy A - Conduct Research (Objectives 1, 2, 4)

Objective 1: Enhance knowledge of the biology and life history of wolffish;

Objective 2: Identify, conserve and/or protect wolffish habitat required for viable population sizes and densities; and

Objective 4: Promote wolffish population growth and recovery.

2.4.1 Recovery Action A1 - Study Life History

Although the subject of considerable research in the Northeast Atlantic, work on the life history of wolffish species residing in Canadian Atlantic waters has been limited, perhaps because they are not the target of a commercial fishery. There is much to learn about how wolffish in the eastern Canadian marine ecosystem reproduce, live, grow and die.

This basic knowledge is the foundation for understanding the population status of wolffish species and subsequently being able to formulate actions required to conserve the species and their habitat so that they are no longer at risk. The recovery objectives set forth by the Recovery Team are broad and we recognize our limitations at present for setting specific measurable objectives without having more complete information about the species; thus the objective for research.

Conduct directed research to study wolffish life history by expanding on available Canadian and international research in the following areas:

  • Reproductive biology;
  • Age, growth, and longevity;
  • Diet and niche;
  • Natural mortality (health condition i.e. diseases, parasites, environmental effects and anthropogenic interactions); and
  • Traditional User Knowledge.

2.4.2 Recovery Action A2 - Study Population Structure within Eastern Canadian Waters

Identification of wolffish population structure, including Designatable Units (DUs), is fundamental to wolffish management. The observed population trends show very different patterns among areas, the decline being greatest on the Labrador Shelf. In contrast, the index for the Scotian Shelf increased to its highest values in the time series in the early 1990s, and has since remained above average. Understanding the reasons for these spatial differences and defining the population unit(s) are key to formulating appropriate recovery and management strategies and actions. To determine spatial variation in the population structure of the wolffish species in eastern Canadian waters, research needs to be conducted on:

  • Age/sex population structure;
  • Migration/seasonal movements and distribution;
  • Wolffish habitat utilization during various life history stages including spawning, nursery, rearing areas and adult feeding;
  • Wolffish abundance with respect to modeling and forecasting abundance; and
  • Genetic, morphometric and meristic characteristics to determine if wolffish form a single DU or multiple Units as a basis for management.

2.4.3 Recovery Action A3 - Identify Biological Reference Points

Fisheries management regimes require the use of a combination of quantitative and qualitative biological reference points (BRP’s) such as biomass estimates or indices that might be considered indicators of a recovered population.

Insufficient data exist for the determination of wolffish BRP’s and these deficiencies require research on their own and with respect to those fisheries in which they are incidentally caught.

In the case of wolffish and other poorly understood species, estimates of population growth and viability under various levels of bycatch will be difficult, if not impossible to determine. In particular, obtaining a measure of natural mortality (M) and longevity is problematic for most marine fish species, including wolffish. In addition, in the case of wolffish, obtaining an accurate estimate of fishing mortality (F) that is required to assure viability is problematic when wolffish are captured in such a diversity of fisheries. Absolute catch is not known, though estimates of total removals can be computed, and subsequently used in the development of Allowable Harm Strategies.

Currently, the best available information for the development of biological reference points is the annual spring and fall research surveys from which biomass indices can be developed. While problematic, due to the lack of understanding of wolffish population dynamics, development of potential BRPs based on historic patterns of wolffish abundance and spatial distribution should be modeled. Given the population fluctuations that occur in wolffish populations, as indicated by research surveys, any abundance and distribution targets that are developed should attempt to incorporate this variability. For example, to develop crude initial reference levels, calculation of the average biomass, corrected for the change in gear, the years when the population was greatest may provide a target biomass index. Similar approaches to modeling of the spatial distribution of wolffish should also be conducted. Spatially, the extent/range of the populations can be used through a presence/absence area estimate, GIS spatial analysis, or other methods. Note again that determining the baseline is problematic and the temporal variation in these parameters should be considered. Since data are not available to define a virgin population, a 50% rule (or some variation upon this) could be employed until more explicit methods are identified. In the future, more refined models should incorporate age-structured population dynamics as additional information on population age-structure and maturity is acquired. With additional data and modeling, the spawning stock biomass and recruitment indices can be employed in the development of BRPs.

Alternatively, consideration should be given to the imposition of a catch limit for each species based on an exploitation index derived from a ratio of catch to biomass index. Further research would be required to determine what level of exploitation would not deter recovery.

2.4.4 Recovery Action A4 - Study Ecosystem Interactions

Altering the species composition, by extinction or decrease in biomass and/or distribution of a wolffish species, within the eastern Canadian marine ecosystem would have unknown effects that could escalate through the ecosystem. For example, they may be the direct prey or predator of commercially important species or wolffish may prey on species that are predators of commercial species. These relationships are poorly understood for wolffish (as for most other marine species). Regardless of their relationship with other species, the disappearance of a wolffish species is a loss to the genetic diversity of the eastern Canadian marine ecosystem. The following research should be conducted to more fully understand wolffish status and its relationships with other species within the eastern Canadian marine ecosystem:

  • Predator/prey interactions;
  • Ocean habitat associations;
  • Abundance in relation to other species;
  • Ecological linkages;
  • The effects of temporal ecosystem disruptions/alterations to critical life history periods of wolffish and their predators and prey; and
  • Possible effects of marine environmental shifts on life history.

2.5 Recovery Strategy B – Habitat Conservation and Protection (Objectives 2, 4, 5)

Objective 2: Identify, conserve and/or protect wolffish habitat required for viable population sizes and densities;

Objective 4: Promote wolffish population growth and recovery; and

Objective 5: Develop communication and education programs to promote the conservation and recovery of wolffish populations and their habitat.

2.5.1 Recovery Action B1 - Identify Habitat, including Critical Habitat

Knowledge of wolffish habitat and how it is utilized is extremely limited. This is not peculiar to wolffish and is generally the case for most marine fish species.

Wolffish historic geographic range defines its potential habitat in eastern Canadian waters (Refer to Part A). Preliminary research has been conducted to identify habitat associations with regard to depth, temperature, substrate and different life history periods have been identified (Refer to Table 1). However, the amount of ocean habitat required on spatial and temporal scales at different periods of the life history for the recovery and survival of wolffish species is not currently known. In addition, changes in wolffish abundance and distribution and seasonal fluctuations may be related to water temperature. Ocean ecosystem habitat complexities for wolffish are not fully understood, therefore species-specific research should be conducted in the following areas:

  • Habitat characteristics and the environmental factors that control or limit distribution, abundance, growth, reproduction, mortality and productivity of wolffish;
  • The physical, chemical and biological characteristics of the ocean ecosystem where wolffish occur;
  • Spatial and temporal foraging and shelter/resting areas to determine habitat associations;
  • Current and historic geographic range and stock size to determine spawning grounds, rearing areas, feeding grounds and the locations of important life history processes;
  • The definition of critical habitat as it pertains to marine finfish, in particular wolffish in eastern Canadian waters in order to determine priority habitat sites. A schedule of studies to identify critical habitat is outlined in Table 22.
Table 22. Recommended studies and associated timelines for the identification of critical habitat, to the extent possible, for A. denticulatus and A. minor
Recommended Studies Start/End Date
Habitat characteristics and the environmental factors that control or limit distribution, abundance, growth, reproduction, mortality and productivity of wolffish. 2006-2007
The physical, chemical and biological components of the ecosystem where wolffish occur. 2006-2007
Spatial and temporal foraging and shelter/resting areas to determine habitat associations. 2006-2007
Current and historical geographic range and stock size to determine spawning grounds, rearing areas, feeding grounds and the locations of important life history processes. 2006-2007
The definition of critical habitat, if possible, for wolffish in eastern Canadian waters in order to determine priority habitat sites. 2007-2008

2.5.2 Recovery Action B2 - Define Measures to Conserve and/or Protect Wolffish Habitat

Effective conservation requires conservation and/or protection of habitat from the unintended effects of human activities on the eastern Canadian marine ecosystem. Legislation, policy, regulations, partnership agreements and stewardship are examples of mechanisms currently in place that can be utilized to protect wolffish and their habitat. Wolffish interact with many different species and these interactions may be critical to their survival, therefore an ecosystem-based approach is recommended. Research should be conducted in the following areas:

  • Threats to wolffish habitat (natural and human induced);
  • Existing or potential activities that may threaten wolffish habitat and the extent to which they can be mitigated;
  • Prioritization of the spatial and temporal habitat needed to be protected to achieve the goal of population recovery; and
  • Potential use of various management options as methods for the conservation and/or protection of wolffish habitat.

2.6 Recovery Strategy C - Mitigate Human Activities (Objectives 3, 4, 5)

Objective 3: Reduce the potential of wolffish population declines;

Objective 4: Promote wolffish population growth and recovery; and

Objective 5: Develop communication and education programs to promote the conservation and recovery of wolffish populations.

2.6.1 Recovery Action C1 - Identify and Mitigate Impacts of Human Activity

It is important for the recovery of wolffish species that the unintended human impacts on their populations and their habitats caused by fishing, offshore oil and gas activities and other potentially detrimental activities be identified and mitigation measures put in place. In addition, offshore mining, military activities, ocean dumping, land-based and atmospheric pollution, and global climate change are emerging issues, all of which may potentially affect the eastern Canadian marine ecosystem and subsequently wolffish populations. Current legislative and regulatory policies, that conserve and protect wolffish and their habitat must function in concert with non-legislative mitigation measures. Research should be conducted where possible to:

  • Identify human impacts on all life stages of wolffish populations and their habitat on spatial, temporal and seasonal scales;
  • Identify impacts and estimate their degree of severity or level of risk associated with their likelihood of occurrence;
  • Identify how impacts can be mitigated both inside and outside the Canadian Exclusive Economic Zone (EEZ);
  • Harmonize international, national, and provincial regulatory changes as they relate to wolffish conservation and incorporate education and stewardship as ways to mitigate human activities;
  • Institute mandatory release of the two threatened wolffish species taken incidentally in all commercial fisheries in a manner that maximizes chance of survival;
  • Promote modifications to gear and methods to avoid the catch of wolffish where practical; and
  • Explore modification of gear/methods to reduce the potential impact on wolffish habitat.

2.7 Recovery Strategy D - Promote Knowledge and Stakeholder Participation in the Recovery of Wolffish Populations and Habitat Conservation and/or Protection (Objectives 3, 4, 5)

Objective 3: Reduce the potential of wolffish population declines;

Objective 4: Promote wolffish population growth and recovery; and

Objective 5: Develop communication and education programs to promote the conservation and recovery of wolffish populations.

2.7.1 Recovery Action D1 – Education and Communication

A key part of the strategy is to increase resource user knowledge and awareness of the plight of wolffish species, their population status, current threats and the actions required to ensure their recovery and long - term conservation. Publication of articles in local and regional newspapers and fishing related magazines, the distribution of wolffish identification material and information on species at risk to the fishing industry and posters along with the production of other educational and advisory materials could all be used to reach a wide audience, specifically harvesters. These materials should be available to the general public as well.

An educational program with both a regional and local component should include the following:

  • The development of a comprehensive community education strategy aimed at resource users including:
  • Identification of wolffish to species level (identification cards); general biology of wolffish and its historic population levels;
  • Safe handling of incidentally captured wolffish in order to successfully release them live into their environment;
  • Awareness of SARA and its importance to the conservation of wolffish;
  • Enhancement of consultative activities including the production of related education and advisory activities; and
  • Encourage resource user community involvement in the implementation of this Recovery Strategy and Management Plan.

2.7.2 Recovery Action D2 - Stewardship

Stewardship, simply stated, means Canadians - including landowners, private companies, volunteer community organizations, and individual citizens - are caring for our land, air and water, sustaining the natural processes on which life depends. Environmental stewardship can be described as the active expression of responsibility to ensure a healthy, diverse and sustainable environment for present and future generations. Implementing stewardship activities is therefore a high priority of this strategy and plays an important part in the conservation and protection of wolffish species and their ocean habitat. Consultation with applicable regional fishery groups will foster and maintain their involvement in recovery actions. Such resource user community involvement and support is critical to the success of the recovery of the wolffish species. This participation will serve as a basis for wolffish stewardship programs. Stewardship initiatives should:

  • Promote the quick and safe release of incidentally caught wolffish to site of capture;
  • Promote the accurate reporting of wolffish catches and subsequent release;
  • Promote the identification of human impacts that may affect wolffish and their habitat;
  • Initiate programs that implement stewardship activities with stakeholders;
  • Provide technical and scientific information to conservation stewards;
  • Enhance consultation activities including the production of related education and advisory materials; and
  • Encourage resource user cooperation and community involvement in the implementation of this Recovery Strategy and Management Plan.

2.7.3 Recovery Action D3 - Consultation and Cooperation with Harvesters, Processors, Scientists, Regulators, Enforcement, Observers, Dockside Monitors, Governments, Aboriginal groups and Other Ocean Users

Consultation with resource users is a key component of the recovery process, required to ensure user involvement in recovery actions. Resource users interact daily with the incidental catch of wolffish species thus, they are provided with a knowledge base from which to design fishing gear to catch fewer wolffish as well as identify methods to safely release them. Such gear modification can be designed to avoid capture through harvesting strategies aimed at reducing encounter rates between wolffish and fishing gear. Therefore, it is important to foster ongoing consultation with resource users and all relevant Canadian jurisdictions. A comprehensive plan for realization of wolffish recovery includes consultation and cooperation amongst a diverse user group (located in each Atlantic Province) including but not limited to:

  • any individuals or groups who may be affected by or may be useful assets in the process of wolffish species recovery and their long-term conservation and protection;
  • Fishing industry,
  • Fishery observers,
  • Aboriginal groups,
  • Provincial and Territorial Jurisdictions,
  • Federal Departments,
  • International Regimes and
  • Academic Institutions

2.8 Recovery Strategy E - Monitoring Human Activities and Wolffish Species (Objectives 3,4)

Objective 3: Reduce the potential of wolffish population declines; and

Objective 4: Promote wolffish population growth and recovery.

2.8.1 Recovery Action E1 - Monitor Wolffish Spatial and Temporal Abundance Patterns

Monitoring the abundance of wolffish species in eastern Canadian waters is essential to ensure that any improvement or deterioration of their status is detected as expediently as possible. This is essential if adaptive management is to be undertaken and be effective. Population size and structure needs to be monitored to discern trends, understand mortality patterns and identify recruitment problems.

Currently, research surveys, particularly stratified-random bottom trawl surveys are used to obtain fishery independent estimates of stock size and to provide quantitative estimates of recruitment. These data provide a basis for interpretation of abundance and distribution patterns that may provide some basis for defining adaptive management measures and recovery actions.

One of the primary objectives for monitoring wolffish spatial and temporal abundance patterns is to determine the effectiveness of any mitigation measures that have been implemented. Basic monitoring allows or enables early identification of unforeseen problems so that corrective measures can be undertaken in order to avoid further impacts. This ensures proper management (i.e. conservation and protection) of fish and their habitat.

Therefore, the recommended actions are to:

  • Utilize research survey data to examine historical, current and future spatial and temporal abundance patterns of each wolffish species; and
  • Utilize harvester’s knowledge to gather spatial and temporal abundance patterns of each wolffish species.

2.8.2 Recovery Action E2 - Monitor Spatial and Temporal Patterns in Natural and Human Induced Mortality

By integrating research survey data with fisheries observer, statistical, dockside monitor and fishing logbook data, changes in wolffish distribution and abundance patterns can be examined to provide a basis for defining appropriate adaptive management measures and recovery actions. This integration of data will aid in the establishment of performance measures to evaluate:

  • Effectiveness of recovery actions on wolffish and their habitat, in particular, effectiveness of the releasing wolffish back to their environment;
  • Management methods on the conservation and protection of wolffish;
  • Habitat protection on the conservation of wolffish; and
  • Education, stewardship, consultation and cooperation on the conservation of wolffish.

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