The idea, and how it is SUPPOSED to work

a very brief overview, with some links to further detail.

What's COSEWIC?

COSEWIC = Committee on the Status of Endangered Wildlife in Canada.
    What is it? It's a federally-mandated committee that is supposed to be arm's length, but it's only armpit length. That's because politicians appoint its members and decide how it works. COSEWIC breaks its own rules. It routinely fudges Reports to make them "reflect" its decisions, but that's illegal: the SARA legislation says {s.21.1}its assessments must be based on the Reports, not vice-versa. Politicians, all the way up to Cabinet, know about the mischief but have not corrected the problem. The most clever part of COSEWIC is that it is controlled by bureaucrats but they get academics to be the figureheads. Smart. Not the academics, the bureaucrats. Not one academic who is a member of COSEWIC has spoken out against its fudging of Reports.

Why do we have an endangered-species List at all?

The species on the planet are responsible for the fact that we have food to eat and oxygen to breathe. Yes, even the oxygen we breathe.
    Loss of any species has unpredictable results, just as introductions can unpredictably threaten wealth or health. Two or three little tiny beetles that hitch a ride to Canada from somewhere else can (unpredictably) cost millions and billions to agriculture or forestry. Other species can threaten human health.
    Loss of any species means loss of something we cannot replace. It means we (humans) are living non-sustainably. For example, if your bank balance is going down day by day, you are not living sustainably in financial terms. If you are lucky enough to have a big bank account, you still take action to prevent living unsustainably.

During the last century and now, we are losing species at a rate unprecedented in human history. We do not know how serious the problems will be. Losing species is only one aspect of the problems we create for ourselves; even before species are lost, ecosystems lose functioning and often that means we lose (because there are, for example, fewer fish or more deserts or less forest).

Therefore, the basic idea that motivates the formation of agencies like COSEWIC is that biodiversity is important. We need an "early-warning-system" that alerts us so we can do something to avoid losing something that we cannot replace. Like a smoke alarm, except for species.
    Agencies and processes are set up to provide that "early warning". The "early warning" (in the form of a Listing on the Endangered Species List) goes to other agencies that then are supposed to identify the measures needed to ensure that we do not lose what we cannot replace.

How is the process supposed to work?

The first step in the process is that someone notices that a species seems to have become more rare. COSEWIC decides whether it merits a look. If so COSEWIC gets one or more scientists to take a careful look, to write a Report (Status Report) indicating how serious the situation is (with reference to the standard criteria) and if possible to indicate what the causes might be.

The careful look is based on data and the 'benchmarks' for the designation levels are more or less internationally consistent. If your investments or your house or simply the money in your pocket lost half its value in a certain amount of time, you would worry. Your credit rating could be excellent, moderate, bad, or you could be bankrupt. Likewise for species: if a population loses more than a specified portion of its numbers in a certain time, it merits a designation.

There are levels of designation, from least-risk to most-risk:

        1. not at risk (not declining enough to meet any of the risk benchmarks)
        2. vulnerable (also called "of special concern")
        3. threatened
        4. endangered
        5. critically endangered
        6. extirpated (gone in a region) or extinct (none left)

As said, those levels are linked to criteria that have been extensively laboured over, and internationally agreed or consistent.

The Report synthesises the available data and recommends a designation. COSEWIC is then supposed to make a designation (pre-SARA) or assessment (post-SARA) based on {SARA s. 21(1)} that Report.

Then, (pre-SARA) any designation Threatened or more serious would require the Jurisdiction/s (the agency/ies responsible for the species at issue) to make a recovery plan. Post-SARA, the COSEWIC assessment has no effect on its own, the Minister and/or Cabinet get to decide whether or not they like what they hear. They can officially add it to the "List", or not, or send it back to COSEWIC (put it back on the hamster wheel).