Giant Threespine Stickleback

Consultations on listing under the Species at Risk Act

Information summary and survey for the consultations on adding Giant Threespine Stickleback to the List of Wildlife Species at Risk as Special Concern – Please provide your input by December 22, 2015.


Let your opinion be heard

Canada’s Species at Risk Act (SARA) provides legal protection for wildlife species at risk to conserve biological diversity.  It also acknowledges that all Canadians have a role to play in the conservation of wildlife species.

Before deciding whether the Giant Threespine Stickleback (Gasterosteus aculeatus) will be added to the List of Wildlife Species at Risk, we would like to hear your opinion, comments, and suggestions regarding the possible ecological, cultural, and economic impacts of listing or not listing this species under SARA.

Adding a species to the List of Wildlife Species at Risk…

The process of listing a species under Canada’s SARA consists of several steps:  it begins with a status assessment by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) and ends with a Government of Canada decision on whether or not to add a species to the List of Wildlife Species at Risk.  Public consultations are conducted to gather the opinions of Canadians and are an important step in this process.

Facts about Giant Threespine Stickleback

Giant Threespine Stickleback
Figure 1. Giant Threespine Stickleback.

The Giant Threespine Stickleback is a freshwater fish, likely descended from the marine Threespine Stickleback (Gasterosteus aculeatus). Freshwater Threespine Sticklebacks typically have three dorsal spines, an anal spine, two pelvic spines and bony plates on the sides of their bodies (Figure 1). Key features of the Giant Threespine Stickleback’s appearance include its unusually large size (~80-85 mm length), a streamlined body, a greater number of gill rakers and bony plates on the sides of the body, longer pelvic spines, and black colouration with silver shading and dark flank bars.

The Giant Threespine Stickleback occurs only within Mayer and Drizzle lakes on Graham Island, Haida Gwaii, British Columbia (Figure 2). Mayer and Drizzle lakes are shallow, acidic, and darkly stained water bodies located in lowlands consisting primarily of Sphagnum spp. bogs and coniferous forest. The number of mature individuals is thought to be in the high tens of thousands for Mayer Lake, and greater than 100,000 for Drizzle Lake.

The male Giant Threespine Stickleback reaches maturity at approximately two (Mayer Lake) or three years (Drizzle Lake). Giant Threespine Sticklebacks typically live up to four years in Mayer Lake and eight years in Drizzle Lake.

distribution map

Figure 2. Distribution of the Giant Threespine Stickleback (in red; was adapted from COSEWIC2013).

Who assigned the Special Concern status to Giant Threespine Stickleback ?

COSEWIC is an independent committee of experts that assesses which wildlife species are in some danger of disappearing from Canada and assigns a status to these species.  It conducts its assessments based on the best available information including scientific data, local ecological knowledge, and Aboriginal traditional knowledge.  COSEWICassessed Giant Threespine Stickleback in Atlantic Canada in November 2013 and designated it as Special Concern.  

Why is Giant Threespine Stickleback at risk?

COSEWIC concluded that threats to Giant Threespine Stickleback is the introduction of invasive species. Other threats include changes in predation regimes (e.g. from Coastal Cutthroat Trout and/or the Common Loon), human disturbance (e.g. forestry operations), and potentially habitat changes caused by

If a species is listed under the Species at Risk Act

If Giant Threespine Stickleback is listed, given the Special Concern status, the prohibitions of SARA (for example, prohibitions against killing, harming, and capturing) would not apply. However, listing would result in the development of a SARA management plan that will include conservation measures for this species in Canadian waters.

We would like to receive your comments on the potential impacts of adding or not adding Giant Threespine Stickleback to the List of Wildlife Species at Risk under SARA, designated as Special Concern.

Your comments are important.

Please fill out the survey:  we want to hear from you.

A copy of the 2013 COSEWIC Assessment and Status Report on the Giant Threespine Stickleback and other information can be found on the SARA Registry.


COSEWIC. 2013. COSEWIC assessment and status report on the Giant Threespine Stickleback Gasterosteus aculeatus and the Unarmoured Threespine Stickleback Gasterosteus aculeatus in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. xiv + 62 pp.

Thank you for completing this survey.

Species at Risk Program, Pacific Region
200-401 Burrard Street
Vancouver, British Columbia, V6C 3S4