Workshop Proceedings Recovery Potential Modeling: Interactions of Allowable Harm, Recovery Targets and Critical Habitat

Marten Koops
Research Scientist
Fisheries and Oceans Canada
PDF (88KB)

The Species at Risk Process In Canada

The intent of the Species at Risk Act (SARA) (2002), and other similar forms of legislation, is to preserve native biodiversity by protecting and restoring species identified as being at risk of extinction (or extirpation). The SARA processes include:

1. Council on the Status of Endangered Wildlife in Canada (COSEWIC) assesses and recommends (to the Government of Canada) listing of species.

2. For aquatic species, the Fisheries Minister must make a decision. The following process is currently in place:

i. DFO Science sector conducts a recovery potential assessment (RPA);

ii. DFO Policy sector conducts a socio-economic assessment;

iii. Consultations are conducted;

iv. Recommendation is provided to the Minister;

v. Minister makes a decision (list, don't list, re-assess).

3. If listed, a Recovery Strategy must be prepared.

Key Features of SARA

Some of the key features of SARA include the identification of recovery targets, which include an abundance target of the number of individuals in a population, as well as a distribution target of the number of populations. Critical habitat, defined as habitat needed to support a recovered population, is also assessed. Additionally, solutions to threats are assessed, which include alternatives such as different actions that do not harm SAR, and mitigations, described as actions that can be modified to reduce harm to SAR. Allowable harm is also analyzed, which is defined as harm that will not jeopardize survival or recovery.

Science Advice for SARA

A Recovery Potential Assessment (RPA) is the best science advice possible, given the available information, to inform listing decisions and recovery planning. The four main components to a RPA include: 1) population status; 2) habitat requirements; 3) threats, including alternative and mitigations; and 4) population modelling.

RPA Modeling

Population modeling is used for the following: allowable harm analysis (AHA); recovery efforts; recovery targets; long-term projections; recovery timeframes; and quantifying habitat needs. Some of the challenges of RPA modelling are that SAR are usually poorly studies species, meaning that population-specific data are often sparse, and that little or no habitat data exists for most species. As well, freshwater species are more likely to be threatened by habitat loss or degradation.

In order to develop an ideal RPA methodology, the following should be considered:

• Does not need time series data

• Assesses harm for all vital rates

• Includes habitat

• Applicable to data poor species

• Handles complex life cycles

• Follows precautionary approach

One way forward is to use Population Viability Analysis (PVA), which is: stage-based; life history based; a stochastic approach; precautionary; includes vital rate sensitivities; and can include habitat.

Allowable Harm Analysis (AHA)

Human-induced harm is a negative perturbation that can target one or more vital rates and life stages. The same concept can be applied to habitat loss.

Recovery Effort

A recovery effort is a positive perturbation that can target one or more vital rates and life stages. The same concept can be applied to the recovery of habitat.

A comparison of allowable harm and recovery efforts shows how much easier it is to harm than to recover a population.

Recovery Targets

Recovery targets can be identified, for both abundance and distribution, based on the concept of long-term demographic sustainability, by using minimum viable population size (MVP) and minimum number of viable populations as thresholds.

In order to quantify a species' habitat needs, the following formula is used:

Recovery Target (MVP) X Area per Individual (API) = Estimate of Minimum Area for Population Viability (MAPV)

A Risk Framework for SAR

The management objectives, as outlined in section 6 of the Species at Risk Act (2002), are:

"...to prevent wildlife species from being extirpated or becoming extinct"

"...recovery of wildlife species that are extirpated, endangered or threatened as a result of human activity"

With long-term persistence of the species as the management objective, recovery targets, critical habitat and allowable harm can be set within the context of the threats and recovery efforts to achieve a probability of persistence for the species (though maybe not for individual populations) that minimizes, or sufficiently reduces, the risk of losing the species.

References

Species at Risk Act (2002). Government of Canada. Accessed on August 23, 2009.
URL: http://laws.justice.gc.ca/en/s-15.3/text.html