When is a species no longer ‘at risk’? Understanding the trumpeter swan’s recovery

It’s a good summer for birds in Alberta. Early this month, we announced that the peregrine falcon has returned to nest on the banks of the Pembina for the first time in half a century. And now, we’re happy to report that another bird species – the trumpeter swan – has been removed from Alberta’s list of Threatened species.

Photo of a group of trumpeter swans.

These two success stories aren’t accidents – they’re the result of our Species at Risk program. This program helps us take action when a species is threatened. To do that, we need two things – a warning that the species is declining, and an understanding of what’s causing the threat.

Numbers aren’t everything – how do we know when a species is at risk?

You might think that a species has to be pretty rare in order to be considered ‘at risk’ – but that’s not necessarily true. What’s most important is whether the population of the species is decreasing significantly over time.

For example, whitebark and limber pine trees are both considered endangered in Alberta. Although there are millions of them in the province, careful monitoring has shown that these populations are slowly – but surely – declining.

What causes species to become ‘at risk’?

A threat to a species can come from a lot of different places. In the case of the peregrine falcon, the decline was caused by exposure to DDT, a pesticide. For the trumpeter swan, the main culprits have been hunting – in the early part of last century – and habitat loss.

Many factors – including development, human activity, disease, invasive species, and climate change – can also cause a species to decline.

‘Concern’, at risk, and endangered – why do we use so many different labels?

In order for us to recognize a threat – and take appropriate action – as soon as possible, it helps to have advance warning. If we wait until a declining species is officially endangered, we lose a valuable opportunity to take action before the situation becomes worse. That’s why our Species at Risk process identifies four different levels of threat to a species:

  • Secure: the species is not threatened.
  • Species of special concern: not an official designation – we’ve identified a decline in the population that requires management attention, but it’s not significant enough for the species to be called ‘threatened.’
  • Threatened: the species require protection and recovery because it is likely to become endangered if limiting factors are not reversed
  • Endangered: this is the most serious classification, for species that urgently require protection and recovery because they’re at risk of disappearing from the province or even becoming extinct.

Right now, 17 species are identified as endangered in Alberta, and 16 are listed as threatened. You can read the full story of how species receive an ‘At Risk’ designation here.

Photo of trumpeter swans

Taking action: how we’ve helped the trumpeter swan recover

We can use many different tools to help a species recover. In the case of the trumpeter swan, the most important step that we took was to implement industrial land use guidelines to protect and reduce disturbance at the swans’ breeding lakes.  With their breeding areas protected, swans began to spread to other areas and they’re now found in many places throughout the province.

Despite this success, our work isn’t done yet. There are still threats – including shorefront development, industrial developments, and collisions with power lines – that might interfere with the trumpeter swan’s recovery. Our current recovery plan for the trumpeter swan (which you can take a look at here) gives us lots of tools to address these issues, including:

  • Plans to secure and protect wetland habitat
  • Rules for development on shorelines
  • Monitoring population growth and nesting success
  • Public education for park visitors, and conservation tools for landowners (like this guide)
  • Tools to reduce collisions with power lines

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s