Despite recent efforts to observe and report observations of herring, anchovy, and even species like dolphins that prey on these fish, we lack robust data that would allow us to assess the status of forage fish.
Author: Karin Bodtker, MRM, Manager, Coastal Ocean Health Initiative, Coastal Ocean Research Institute
Reviewers: Jeff Marliave, Senior Scientist, Howe Sound Research Program, Coastal Ocean Research Institute
Ramona de Graaf, Forage Fish Biologist, Sea Watch Society
Banner Photo Credit: Sarama
This past summer there was much excitement in Howe Sound over anchovy sightings. Large schools of adult anchovy were occasionally observed from May through July, and larvae or very small young fish (also called YOY, young of year) were observed into November, so much so that it made the news. Sport fishers, biologists, and citizen scientists all reported seeing more anchovy in 2016 than in 2015, when reports precipitated action to identify the fish, as anchovy hadn’t been seen for 10 years prior. In 2016 anchovy were observed in locations all across the outer part of the Sound from Horseshoe Bay to Gibsons, and around Bowen Island and the Paisley Group. They were also reported in the Caulfield area of West Vancouver, in False Creek, and in Indian Arm (Figure 1).
Other species of forage fish in Howe Sound include herring, Pacific sand lance and surf smelt. Herring and their eggs, called spawn, have been witnessed by many in recent years in upper Howe Sound, and diligently recorded over the past six years by John Buchanan, citizen scientist. Beach spawning habitat for Pacific sand lance and surf smelt was assessed and mapped around Gambier, Keats, and Bowen Islands in 2014.
Why is it important?
The excitement is warranted because the status of forage fish populations can be an indicator of the health and productivity of nearshore systems in our marine environment. Forage fish are small schooling fishes, aptly named because, as a vital link in the food web, they provide abundant forage for upper trophic feeders, such as salmon, birds, and seals, for their entire life. They are also known as bait fish to anglers. While northern anchovy are occasional visitors to Howe Sound, Pacific herring, surf smelt and Pacific sand lance all contribute to a staple diet for many Howe Sound species. Eulachon and sardines are also examples of forage fish.
Most forage fish species depend on nearshore and intertidal habitat for their survival, especially when it comes to reproduction. Herring spawn (lay eggs) in intertidal and subtidal areas on vegetation such as eelgrass and seaweed and even manmade structures like piers (Figure 2). Pacific sand lance and surf smelt spawn on pebble and sand beaches just below the high-tide line. Small fish also depend on subtidal areas such as kelp forests and eelgrass beds for rearing. Howe Sound is lacking the bull kelp beds that are typical elsewhere in the Pacific Northwest and its steeply-sloped banks mean that eelgrass beds have always been limited in their distribution. In some places, subtidal eelgrass has suffered significantly due to log handling and booming practices that starved these habitats of both light and oxygen. All the species that depend on healthy nearshore and beach habitat are vulnerable to impacts from shoreline development.
First Nations Connections
Notes on forage fish from the British Columbia Language Project 1976
“Smelt (surf smelt – schá7kwem) was an important species of food for the Squamish Indian people. In the summer months, the people travelled to Point Grey to collect smelts which spawned on the sandy beaches around Jericho Beach and English Bay.”
Different words in the Squamish language refer to Squamish River eulachon (s7áynixw) and Fraser River eulachon (swí7ew). A word meaning “time of eulachon” (tem-s7áynixw) refers roughly to a time period corresponding with April.
“The Squamish people recognize two sub-species of the species that is recognized scientifically as Thaleichthys. The first sub-species, s7aynixw, the Squamish River eulachon, is apparently found only at the head of Howe Sound and in the Squamish River. This species is ‘four to five inches long,’ is ‘more silver-blue in colour’ than the Fraser River eulachon and has a ‘higher oil content’ than the Fraser River eulachon. Apparently both sub-species spawn during the month of April.”
– content from “Utilization of fish, beach foods, and marine mammals by the Squamish Indian people of British Columbia,” Bouchard.003, Survey of California and Other Indian Languages, University of California, Berkeley, 1976.
What is the current status?
In the middle of July 2015, John Buchanan, citizen scientist, witnessed a fish mass that seemed about half a kilometre long and 100 metres wide at Porteau Cove and “counted 20 seals that were working very well together in a line that basically cut off a section of the school and penned it in a small cove right in front of the beach where the campsites start.” These fish were northern anchovy. Their presence in Howe Sound has been recorded in seven different years since 1971, including 2015 and 2016 (Figure 3).
With identification confirmed by a taxonomist, observations of anchovy submitted by scientists, divers, and citizen scientists are recorded in a database of marine life held by the Vancouver Aquarium Marine Science Centre. This unique database holds the only records of anchovy observations that we are aware of for Howe Sound.
The locations of herring spawn aggregations also shift from year to year. DFO calculates a cumulative herring spawn index which ranks and classifies each kilometre of herring spawning habitat according to the long-term frequency and magnitude of spawns over time. Spawn locations in Howe Sound are classified as medium, minor, and low, because they rank below the 70th percentile compared to coast wide records of spawn (Figure 4, left panel). Citizen scientist, John Buchanan, has been surveying the north end of Howe Sound and recording herring spawn observations each spring since 2010. His findings since 2011 are mapped (Figure 4, right panel).
Herring spawn early in the year and multiple spawn events can extend the period of spawn activity. John Buchanan observed herring spawn in upper Howe Sound as early as January 9th in 2014. DFO data illustrate the variability in the timing of herring spawn. The data also suggest that spawning may be occurring earlier in recent years, but this could be an artifact of limited DFO survey effort in Howe Sound, as data provided by J. Buchanan suggest that the range of spawn dates is still quite broad (Figure 5).
In an effort to identify sensitive beach spawn habitat for surf smelt and Pacific sand lance, Ramona de Graaf, of the Sea Watch Society, surveyed and recorded suitable and not suitable habitat on Gambier, Keats, and Bowen Islands in Howe Sound in 2014 (Figure 6).
Commercial fisheries for forage fish are not common in Howe Sound. Commercial catch of herring in Howe Sound occurred in only seven years between 1950 and 1980 and has not occurred since then. Catches ranged from one to 51 tonnes. Surf smelt are currently managed by DFO for both commercial and recreational fisheries and commercial fisheries for surf smelt have existed since the mid-1800s. Much of the historical catch in B.C. came from Vancouver beaches. Recreational fishing for surf smelt has increased significantly since the early 1990s, especially on beaches of the Lower Mainland, rivers of Alberni Inlet, and docks in the Prince Rupert area. The most recent stock status report is dated 2002 and the most recent Integrated Fisheries Management Plan is for April 1, 2012 to March 31, 2014.
Threats to beach spawning fishes are numerous, but the number one threat is hard armouring of the beaches; seawalls, riprap, and boat ramps. As sea level rises these fish may lose their place to lay eggs due to a phenomenon known as coastal squeeze (see illustration in Shorelines article). Activities including improper shoreline development, marine shellfish aquaculture in the foreshore, and diversion of sediment-bearing streams through culverts can render beaches unusable for spawning. These shoreline modifications can also limit sediment exchange in the shallow subtidal where sand lance is known to burrow. Acute oil spill events and chronic oiling are deadly as oiling suffocates embryos. Climate change will further affect the survival of forage fish because increasing ocean acidity and increasing sea surface temperatures will likely affect larval survival. Changes in the timing of spring bloom have already been linked to the success of herring larval recruitment in the Strait of Georgia. In particular, the mismatch between spawn timing and the start of the spring plankton bloom was found to have a substantial impact on survival and production of herring.
What can you do?
Individual and Organization Actions:
- Prevent sediment, chemical or oil run-off from your property. Oiling from vessel operations near beaches can potentially cause mortality of incubating forage fish eggs. Siltation of beaches can smother tiny eggs.
- Avoid building breakwaters, riprap, seawalls, docks or pilings near beach habitat that may support forage fish.
- Retain natural shoreline vegetation because shade from overhanging vegetation keeps fish eggs moist in the summer and insects from overhanging vegetation are a source of food for forage fish. The roots of natural vegetation on the foreshore and coastal bluffs also help to bind the soil and minimize erosion. Removing shoreline vegetation increases temperatures within the spawning gravel and removes a food source for young fish. On hot summer days, without shade, eggs can’t survive.
- Re-establish native shoreline vegetation if absent.
- Trim trees to improve your view instead of removing them. This helps to retain the stability of the bank and slope soils and to maintain shade on the beach.
- Set back any new development from the bluff or foreshore, to minimize the future need for foreshore protection.
- Manage storm water and maintain vegetation above bluffs to avoid soil saturation and slumping.
- Retain natural drainage patterns and design storm water systems so that water is cleaned before it enters the foreshore.
- Use soft shore or Green Shores approaches rather than hardening the shoreline.
- Volunteer with the BC Shore Spawners Alliance
Government Actions and Policy:
- Increase efforts to educate land owners on foreshore regulations.
- Monitor and enforce the legislation (B.C. Land Act) that prohibits changes below the high tide line without lease or license of occupation.
- Prioritize and fund research, monitoring, and protection of forage fish habitats.