Assessment of Pacific sand lance ( Ammodytes hexapterus ) and surf smelt ( Hypomesus pretiosus ) spawning at the ecologically restored Jericho Beach

• Main Authors: Chow, Cassidy, Park, David, Colonel, Mikalyn Trinca, U, Nuno
• Format: Text
• Language: English
• Published: The University of British Columbia 2020
• Subjects: Canada; Pacific; Orca
• Online Access: https://dx.doi.org/10.14288/1.0390278; https://doi.library.ubc.ca/10.14288/1.0390278

Vancouver BC is one of the most rapidly growing cities in Canada. With an abundance of coastal waters and shore lines and its population only set to increase in the next decades, it is important to assess the impacts that increasing urbanization will have on important coastal marine ecosystems. Intertidal zones and beach shore front provide significant biological and societal value through supporting native marine life and providing scenic space for recreational activities. In 2013, the City of Vancouver enacted a plan to restore vital intertidal areas of Jericho Beach to support native wildlife and increase urban biodiversity. One of the main goals of the project was to create an ideal habitat for local forage fish, a small, but vital intermediate fish in the British Columbian coastal ecosystems. Forage fish, such as Pacific sand lance ( Ammodytes hexapterus ) and surf smelt ( Hypomesus pretiosus ), help link energy sources from low-level trophic levels such as zooplankton to higher levels including larger fish, seabirds, marine mammals, and even BC’s iconic Orca whales. Furthermore, forage fish populations have been dropping in the Burrard Inlet, increasing the need for urban spawning areas to increase population sizes. In 2016, the City of Vancouver launched the Biodiversity Strategy aimed at increasing Vancouver’s wildlife and natural ecosystems through projects much like the 2013 Jericho Beach Restoration. This study aimed to investigate whether the Jericho Beach Restoration Project 2013 has been successful in hosting forage fish populations by conducting a quantitative comparison of Pacific sand lance ( A. hexapterus ) and surf smelt ( H.pretiosus ) spawning presence at two opposing sites of the beach: Site 1 - the Restored Beach and Site 2 - the unrestored Jericho Beach over one spawning season. Sediment samples were collected between January 2020 through February 2020 and processed using sieving methods and the vortex method. Abiotic parameters such as slope, sediment grain size, and salinity were measured. Laboratory analysis of sediment samples resulted in the stark absence of forage fish eggs of any kind during this time, despite sediment size analysis indicating similar and ideal sediment size ranges from 0.5mm - 2mm at each site. Ultimately, the results demonstrate that there was no forage fish spawning during the sampling period. Determining the performance of past ecological restoration projects, such as the Jericho beach restoration, may provide insight into how to improve new ones under Vancouver’s Biodiversity Strategy, and hopefully increase biodiversity and urban wildlife as a whole. We suggest further year-round monitoring of forage fish spawning on all coastal Vancouver beaches in the Burrard Inlet to identify whether spawning is present at all in the area.