Does the road to recovery of Pacific herring

go through eelgrass?

Tessa Francis, PhD

University of Washington Tacoma

Puget Sound Institute

Pacific herring Clupea pallasi

Herring are foundational species in the Puget Sound

Marbled murrelet: 60%

Tufted puffin

Herring are declining in Puget Sound

0

500

1,000

1,500

2,000

1973 1983 1993 2003

Ad

ult

Herr

ing

Sp

aw

ners

(t

on

s)

Year

Quartermaster Harbor

0

3,000

6,000

9,000

12,000

15,000

18,000

1973 1983 1993 2003Ad

ult

Herr

ing

Sp

aw

ners

(to

ns)

Year

Cherry Point

Does the road to herring recovery go through eelgrass?

Are herring limited by the availability of eelgrass for spawning?

Are herring egg survival rates highest on eelgrass?

Measuring herring egg mortality

Is egg survival higher on eelgrass? P

rob

ab

ility

of ha

tch

ing

Elliot Bay PM HH CP QB

Shelton, Francis et al. 2014 MEPS CP HH QB QM

Herring are foundational species in Puget Sound.

Herring hatch rates vary more by SITE than by SUBSTRATE TYPE.

Predation is a major source of egg mortality at most spawning sites, but does not explain site differences in egg hatch rates.

Thank you!

Tessa Francis Puget Sound Institute tessa@uw.edu