Wildlife At Risk in British Columbia
A brochure series which will eventually include brochures on other Red 
and Blue listed species, including fish, invertebrates and plants, and on 
ecosystems.  Produced by the Ministry of Environment, Lands and Parks, 
Wildlife Branch, 780 Blanshard St. Victoria, BC V8V 1X4. For copies of 
this brochure, write to the Wildlife Branch. Funded by Corporate 
Resource Inventory Initiative and Ministry of Environment, Lands and 
Why are Salish Suckers at risk?

Salish Suckers are endangered because they have a very restricted 
distribution range and their habitat is rapidly being degraded by human 
land uses. The world distribution of this inconspicuous fish is confined to 
a small area in northwestern Washington state and the adjacent Fraser 
Valley of British Columbia. This contrasts sharply with the range of its 
nearest relative, the Longnose Sucker, which is found across northern 
North America and into Siberia.

In British Columbia, the Salish Sucker is found only in a few small 
streams in the heavily settled Fraser Valley south of the Fraser River, in 
the vicinity of Langley and Aldergrove. These watersheds have been 
adversely affected by forest removal and farming for many decades, and 
are now threatened more than ever by accelerating human population 
growth and land development.

Some of the streams arise in urban areas where their headwaters are very 
polluted. Human impacts on these fragile streams include pollution from 
sewage, pesticides, fertilizers and manure; removal of over-hanging 
streamside vegetation which provides hiding cover and prevents over-
heating of the water; and alteration of streamflows by ditching, diversion, 
irrigation use, and expanding storm sewer systems. A common problem 
is flash-flooding during short periods of high rainfall in autumn and 
winter, and extremely low flows and high water temperatures in 

In recent years the Salish Sucker has apparently disappeared from at least 
two streams in this area and populations have declined in others. The 
long term outlook for these streams is very pessimistic. Scientists 
studying the sucker have concluded that it is destined for extinction in 
British Columbia if action is not taken soon to protect its habitat.

What is their status?

The Salish Sucker has been found in only three sites outside of British 
Columbia: a reservoir, a lake and a slough, all in Washington state. Those 
habitats are thought to be fairly safe from development.

In 1992, BC Environment biologists, with support from the Habitat 
Conservation Fund, intensively surveyed 34 streams south of the Fraser 
River and west of Hope. Salish Suckers were found in only 5 streams. 
None could be located in two streams where they formerly lived – the 
Campbell River which flows into Semiahmoo Bay, and Salwein Creek, a 
tributary of the Vedder River. Very few suckers were present in the 
Salmon River (a tributary of the Fraser) where they were formerly 
common. Although suckers were detected in four small Canadian 
tributaries of the Nooksack River, which drains into Bellingham Bay, 
their status there is of some concern. During the 1992 survey, only one 
specimen was found in Bertrand Creek, only juveniles in Cave Creek (a 
tributary of Bertrand), and the population in Fishtrap Creek was severely 
impacted by land development. Only one stream, Pepin Creek, had a 
healthy population of both juvenile and adult suckers, probably because 
a portion of its course is through protected parkland.

The small distribution range and downward trend in habitat quality and 
sucker numbers combine to place this fish in the category of highest risk. 
The Nature Conservancy system used by the Conservation Data Centre 
of BC Environment ranks the Salish Sucker in Category 1, “critically 
imperiled because of extreme rarity,” both globally and provincially. 
Nationally, the Committee on the Status of Endangered Wildlife in 
Canada (cosewic) classifies it as Endangered. By whatever measure, the 
Salish Sucker is indeed among the most threatened members of our 

What do they look like?

Typically fish-shaped, the Salish Sucker has an elongated, cylindrical, 
torpedo-shaped body. Specimens up to 24 centimetres long have been 
captured in Fraser Valley streams, but the majority are much smaller. 
Like other members of the sucker family, these fish have a rounded 
toothless mouth on the underside of the head, slightly back from the tip 
of the nose. The mouth has fleshy lips covered with small projections 
called papillae for sensing food, and is designed for sucking up food 
from the streambottom.

Like its close relative the Longnose Sucker, the Salish Sucker has a fairly 
long snout ending in a rounded point, small scales, a moderately forked 
tail with rounded tips, and a large anal fin. The dorsal fin has 9 to 11 rays 
(supports). The usual colouring is olive with copper tones on the back 
and upper sides, and cream to white on the lower sides and belly. This 
protective colouring helps the sucker to blend into its environment no 
matter what angle it is viewed from. The unpaired fins are generally dark 
in colour, while the paired fins have an amber tint. At breeding time, 
both males and females develop a broad rose- or wine-coloured band 
along their sides. This is most vivid in the males.

Largescale Suckers occur in the same streams as Salish Suckers but can be 
distinguished by their larger scales and dorsal fins with 13 to 15 rays. 
Trout and juvenile salmon also frequent these streams, but differ from 
suckers in having a mouth with jaws and teeth at the front of their head, 
and a small fleshy fin, the adipose fin, on the back just forward of the tail. 
Dace are also present, and have sucker-like mouths, but their lips do not 
have papillae.

What makes them unique?

The Salish Sucker is a distinctive, semi-dwarf form of the Longnose 
Sucker. Its distribution range is separated from that of the Longnose 
Sucker by a gap of 45 kilometres, which prevents any genetic contact 
between the two forms.

The Salish Sucker is believed to have evolved its distinctive 
characteristics while isolated from other Longnose Sucker populations 
during the ice age. At the height of the last stage of the Pleistocene 
glaciation, ice completely covered the present Fraser Valley and extended 
south over Puget Sound to the vicinity of Olympia, Washington, and 
even further south in the Cascade Range. The Salish Sucker was probably 
isolated for thousands of years in a non-glaciated “refugium” between 
the Puget Sound ice sheet and the Columbia River. As the ice sheet 
melted back, the fish were able to expand northward into the Fraser 
Valley through various lowland streams or lakes which were periodically 

During its period of isolation, which has continued to the present day, 
the Salish Sucker gradually assumed the characteristics which distinguish 
it from typical Longnose Suckers. These include larger scales, a deeper 
head, shorter snout, and a lip that is not as broad as that of the Longnose 
Sucker. It also became adapted to environmental conditions that are 
peculiar to the Lower Fraser Valley.

The Canadian population of Salish Suckers is also somewhat unusual in 
being entirely confined to small streams. Throughout most of their range, 
Longnose Suckers spend much of their life in lakes, entering streams 
primarily to spawn.

How do they reproduce?

Spawning activity of Salish Suckers has been seen in Fraser Valley 
streams mostly in April, when water temperatures were 7 to 8°C, but 
may also occur later in the season. Specimens in spawning condition have 
been seen as late as July and August. Spawning usually takes place in the 
upper reaches of streams, at sites having a moderate current, a water 
depth of 15 to 30 cm, and a stream bottom comprised of fine gravel.

Spawning activities of Salish Suckers have not been studied in detail. 
However, female Longnose Suckers eject thousands of tiny white eggs a 
few at a time into the water. These have a sticky surface and adhere to 
gravel on the bottom of the creek. As the eggs are released, one or more 
male suckers release sperm into the water to fertilize them. Longnose 
Suckers produce 17 000 to 60 000 eggs per female, the number varying 
with the size of the fish. Salish Suckers, being smaller than average 
Longnose Suck-ers, probably have egg numbers near the bottom of that 

Based on studies of the Longnose Sucker, eggs hatch about two weeks 
after spawning and the fry stay among the gravel for another one or two 
weeks. The Salish Sucker may have similar characteristics, but little is 
known about its life history and proper studies are badly needed.

Suckers do not build a nest or care for their eggs or young. Many eggs 
have to be produced to ensure survival of a few to adult age. Salish 
Suckers probably do not breed until at least three years of age, but this 
also needs confirmation.

What do they eat?

Suckers have mouths designed for vacuuming up food from the bottom 
of streams or lakes, and their diet reflects this specialization. The papillae 
on the lips help to detect suitable food items. Suckers feed entirely on 
invertebrate life and do not prey on other fish.

In British Columbia, only 10 specimens of the Salish Sucker, all adults, 
have ever been examined to see what they had eaten. All contained many 
remains of freshwater insect larvae called chironomids. These are the 
larvae of two-winged flies known as midges. The diet of young Salish 
Suckers is not known.

Longnose Suckers eat a variety of bottom-dwelling organisms such as 
snails, crustaceans, insect larvae, worms, and occasionally fish eggs. 
Salish Suckers probably eat a similar variety of items, however this 
requires more study. Information on the diversity and abundance of food 
organisms in small streams inhabited by Salish Suckers is not available. 
Human impacts on these little creeks could have serious effects on the 
suckers’ food supply.

Where do they live?

In British Columbia, Salish Suckers live in the upper reaches of small, 
gently flowing streams at an elevation of 40 to 110 metres above sea level. 
Headwater areas preferred by Salish Suckers, where not polluted, tend to 
have cooler, clearer water and faster flows than the lower reaches. This is 
in keeping with the preference of their nearest relative, the Long-nose 
Sucker, for clear, cold waters. The Fraser Valley streams have high flows 
in winter, but may be reduced to a mere trickle in summer. In one stream 
sampled in the summer of 1992, Salish Suckers were restricted to shallow 
pools separated by dry creekbed. Under these conditions, the likelihood 
of survival is poor.

Salish Sucker streams in the gently rolling Fraser Valley are mostly 2 to 7 
m wide, less than one metre deep, with silt, sand or gravel bottoms and 
fair-ly slow currents. Habitats in them have been classified as pools 
(deepest areas with little or no current), glides (moderate depth with slow 
current) and riffles (shallow, relatively fast water). Juvenile Salish Suckers 
use all of these habitats while adults are found mostly in glides and 
pools. Riffles with fine gravel bottoms are preferred for spawning.

The Fraser Valley streams flow mostly through farmland or small 
acreages which have been cleared of trees. However, tall grasses, rushes 
and brambles are common along the stream-banks, except in grazed 
pastures. Pondweeds and other aquatic plants occur in some sections. 
During surveys in 1992, BC Environment biologists found Salish Suckers 
most often among instream vegetation or along streambanks where over-
hanging vegetation provided some cover. This was particularly true for 
juvenile fish. Other fish living in Fraser Valley streams with Salish 
Suckers include sticklebacks, juvenile Coho Salmon and Steelhead, 
Cutthroat Trout, lampreys, Brassy Minnows, and the Nooksack Dace (a 
close relative of the Longnose Dace).

Known populations of Salish Suckers in Washington occur in a slough, a 
reservoir and a lake – habitats that are quite different than in British 
Columbia. However, it is likely that this sucker also resides in streams in 
the Nooksack River system in Washington.

What can we do?

Unfortunately, most people have never heard of the Salish Sucker. Yet 
without strong public support for protection of its dwindling habitat it 
seems destined for early extinction in Canada. Even though salmonid 
fishes are also found in the Salish Sucker streams, habitat protection 
provisions in the Fisheries Act have failed to give these streams the 
protection they need. Laws alone will not save the Salish Sucker. The first 
and most urgent need is for widespread public awareness of the plight of 
this unique fish, and of other species such as the endangered Nooksack 
Dace which share its fragile and threatened habitat.

Threats to Salish Sucker streams are so many and so varied that many 
kinds of action are needed. Most of the land developments which affect 
these streams are regulated at the municipal level of government, so 
increased attention is needed at that level. Land owners along the 
streams have a special stewardship responsibility and must become 
involved in habitat protection and improvement.

There is an urgent need for better control of sewage, pesticides and other 
pollutants and for design of stormwater systems which prevent flash 
flooding. Prevention of ditching, diversions and other stream alterations, 
and maintenance of riparian (streamside) vegetation, particularly trees 
and shrubs, are also priority needs. Positive activities could involve 
habitat acquisition, tree plant-ing, spawning habitat development, and 
cooperative agreements with landowners. More information is also 
needed on the life history and ecology of Salish Suckers so that their 
streams can be better managed, and even enhanced.

The streams that are home to Salish Suckers have many values. These 
ribbons of aquatic and riparian habitat support a diversity of life, provide 
recreational opportunities, and enrich the landscape with their beauty. 
They would be worth saving even if no endangered species were present.

The public can play an important role in Salish Sucker preservation by 
learning more about this fish and its habitat, and by supporting programs 
to maintain and improve the quality of the streams it lives in.