Pacific herring "recovery": Identifying causes of decline of an indicator species
Tessa Francis UW Tacoma Puget Sound Institute Collaborators
Ole Shelton, NOAA NWFSC Phil Levin, NOAA NWFSC Greg Williams, NOAA NWFSC Kurt Stick, WDFW Adam Lindquist, WDFW Megsie Siple, UW Shannon Hennessey, UW
Meet the fish.
Pacific herring Clupea pallasii
NOAA Fisheries West Coast
Surf smelt Hypomesus pretiosus
NOAA Fisheries West Coast
Sand lance Ammodytes hexapterus
photo by Ground Truth Trekking BRANDON COLE / WWW.BRANDONCOLE.COM Redorbit.com
Forage fish are more valuable in the water than out.
Rhinoceros Chinook auklet: 70% salmon: 80% Marbled murrelet: Lingcod: 95% 60% Photo by Peter Hodum
Tufted puffin
Harbor Orcas Seals: 80% Forage fish are 30-60 times more valuable in the water
Direct value Supportive value
$0.4 – 0.8 $25 million million
Source: DFW 2008, TCW Economics; LenFest Forage Fish Task Force Report
Habitat matters
• Herring population is 2x more stable because of habitat diversity.
• Shoreline development degrades forage fish spawning habitat. • Higher egg mortality • Higher temperatures • Loss of fresh sediment supply
What is their status?
?
?
photo by Ground Truth Trekking What is their status?
Puget Sound Herring Biomass 18,000
15,000
12,000
9,000 TONS
6,000
3,000
0 1973 1978 1983 1988 1993 1998 2003 2008 2013 2018 YEAR There are major challenges
1. We don’t know population status of photo by Frank Varga surf smelt or sand lance. • How many are there? • How many do we need?
photo by Ground Truth Trekking 2. We don’t know why herring are declining in some areas. Herring • Habitat impairment/loss • Predation • Prey • Disease • Disturbance
Are herring habitat limited? 33% of shoreline altered
Eelgrass bed trends (2004-2009) 25% of shoreline No change armored
Decrease 2005-2010 Increase Rate of new armoring: 1.8 km/yr
1. Which spawning habitat is the highest quality?
2. Are herring limited by the amount of this high quality habitat? Puget Sound Herring Spawning Sites
1. Egg Loss on spawning habitat
2. Egg survival in the lab Egg survivorship varies across Puget Sound Probability of hatching Proportion hatched Proportion hatched Proportion impervious surface imperviousProportion Proportion armored shoreline armored Proportion Potential drivers of of egg mortality drivers Potential
Egg loss rate Mean wave weight (m) weight Mean wave
Historical Habitat Analysis
Nearshore Habitat Surveys
Point Data: Spatial location Annual Sampling (Winter / Spring) Presence / Absence of >30 vegetation categories Consistent methods (1972-present)
Eelgrass (presence/absence) Cherry Point Eelgrass Temporal Change in Eelgrass 1972-1977 vs. 2008-2012
Cherry Point Port Madison Temporal Change in Eelgrass 1972-1977 vs. 2008-2012
Cherry Point Port Madison What actions are we taking?
• Puget Sound Institute convened a panel of experts to fill key information gaps; research to identify limits to herring recovery
• Puget Sound Partnership tracks Pacific herring indicator.
• PSEMP has prioritized measuring sand lance and surf smelt abundance.
• Dept of Fish & Wildlife is taking a precautionary approach with fisheries management.
• Dept of Fish & Wildlife requires HPA permit to develop shorelines.
• NWSI funds monitoring and research in support of forage fish.
• MRCs map, monitor and restore spawning beaches. Next Steps • Impacts of predation on herring eggs and adults
• Population model
• Changes in spawn timing
• Quantify links between humans and herring
• Impacts of stock structure on food web
Thank you.
Tessa Francis Puget Sound Institute [email protected]
Predation is a major source of herring egg mortality
Proportion of Proportion Eggs Lost
cage no cage Experimental Treatment Eelgrass Sargassum Red branched algae
Key Indicators of Ecosystem Health Food web connections
Predators
Forage fish
Zooplankton
Phytoplankton Key Indicators of Ecosystem Health Human impacts
Shoreline development Human Activities Contaminants/pollutants Water quality Key Indicators of Ecosystem Health Human wellbeing
Psychological wellbeing Human Wellbeing Sense of place Cultural traditions