Diadromous Fish Assemblage Assessment in the Estuary, ME

Kayla Smith James Sulikowski, Ph.D. and Carrie Byron, Ph.D. Dept of Marine Sciences Saco River Estuary

• Nursery ground • Foraging stop-over site for migratory fishes • 60 marine, diadromous and freshwater species observed since 2007 (J. A. Sulikowski, unpubl. data)

Introduction Methods Results Conclusions Future Work Previous Research o Reynolds and Casterlin, 1985, Hydrobiologia – n = 18 o Furey and Sulikowski, 2011, Northeastern Naturalist – n = 24 o Little et al. 2013, Journal of Applied Ichthyology Gear types used include: Hook and line Plankton tows Light and modified lobster traps Beam and otter trawl Seine, D-frame and gill netting Settlement collectors Long line Introduction Methods Results Conclusions Future Work Diadromous fishes

• Provide important links between coastal watersheds and the Atlantic Ocean • Economic and cultural value

Introduction Methods Results Conclusions Future Work Diadromous fishes in the Gulf of 12 species

Introduction Methods Results Conclusions Future Work Status in the

• Complicated life history • Severe population declines • Lost connections = impaired ecosystems • Need: better define interactions and linkages between species

Introduction Methods Results Conclusions Future Work Does fish species diversity, richness and abundance vary along a river gradient in the Saco River estuary?

Is there interannual variability in the fish community?

Introduction Methods Results Conclusions Future Work River Channel Sampling

10

8

6

4 2

Introduction Methods Results Conclusions Future Work Channel Gill nets Marsh 4”“Multi and 6”-mesh” mesh

3” 1” ¾”

Michigan Sea Grant

Introduction Methods Results Conclusions Future Work Upper Middle Multi-mesh

• Multi-mesh • 4” mesh Multi-mesh Lower • Multi-mesh • 4” mesh Multi-mesh

• Multi-mesh • 6” mesh Gill nets 2012 2013

Introduction Methods Results Conclusions Future Work Sampling Methods – Gill nets • Set between 2 and 4 a.m. • Pick-up between 6 and 8 a.m.

• Temperature • Salinity • Dissolved oxygen

Introduction Methods Results Conclusions Future Work Beach Seining 2010-13

Introduction Methods Results Conclusions Future Work Fish Metrics and Abundance

Catch-per-unit-effort (CPUE)

N = Number of fish caught t = Time of net in water CPUE = N/t/ln/hn ln = Length of net hn = Height of net mesh area

Introduction Methods Results Conclusions Future Work Biodiversity Indices

Shannon - Wiener Diversity Index

풔 H’ = diversity index, 푯′ = − 풑풊 퐥퐧 풑풊 S = total number of species 풊=ퟏ pi = proportion of S represented by the ith species Simpsons diversity index

퐧(풏 − ퟏ) n = total number of individuals of a 푫 = ퟏ − single species 퐍 (푵 − ퟏ) N = total number of individuals caught

Introduction Methods Results Conclusions Future Work Preliminary Results – Gill nets

• 17 trips June through September – 2012 (5) – 2013 (12) • 230 hours fished – Average soak of 3.7 hours • 353 fish caught – 13 species, juveniles and adults – 89 % diadromous fish

Introduction Methods Results Conclusions Future Work Salinity Gradient

20 A 18 17 16

14 )

ppt 12 10 B B

Salinity ( Salinity 8 6 6 6 4 2 0 Upper Middle Lower Upriver Mouth Introduction Methods Results Conclusions Future Work Fish Abundance

20 0.006 B 18

0.005 16 14

0.004 )

12 ppt 10 0.003

B (CPUE) effort unit

8 - Salinity ( Salinity

0.002 per 6 -

4 Catch A 0.001 2 0 0 Upper Middle Lower

Introduction Methods Results Conclusions Future Work Fish Abundance

100%100 90%90 80%80 Alosa spp. 70%70 Acipenser spp. 60%60 Morone spp. 50%50 Other 40%40 30%30 20%20 10%10 0 Upper Mid Lower

Introduction Methods Results Conclusions Future Work Fish Abundance

100%100 90%90 80%80 Alosa spp. 70%70 57% 57% Acipenser spp. 60%60 87% Morone spp. 50%50 Other 40%40 16% 30%30 43% 20%20 17% 6% 10%10 2% 0 Upper Mid Lower Introduction Methods Results Conclusions Future Work BiodiversitySpecies Richness Indices

Shannon Diversity Index Simpson's Index of Diversity Species Richness (n)

2 14 1.81 1.8

12 12

1.6 10 1.4 10 1.23 1.2 1.02 8 1 0.78 6 0.8 0.66

0.6 0.52 3 4 Diversity Indices Diversity 0.4 Richness Species 2 0.2 0 0 Upper Middle Lower Station Introduction Methods Preliminary Results Conclusions Future Work Results – Beach Seining

227 seines 11,544 fish 4% Diadromous

Introduction Methods Results Conclusions Future Work Fish Abundance 2010 2011

2012 2013

Introduction Methods Results Conclusions Future Work Life History Groups

100% 11%

90%

80% 70% 61% 33% 60% Freshwater 50% Estuarine 40% Marine 30% 56%

20% 33% Percentage of Catch Catch of Percentage 10% 0% 6% fresh and oligohaline (0-5ppt) mesohaline (5-18ppt)

Water classifications from the EPA’s Volunteer Estuary Modeling Manual. Fish species life history classifications categorized by Dionne et al. (1999) and FishBase v. 04/2014. Introduction Methods Results Conclusions Future Work Summary

• 33 fishes and 4 crustacean species – Gill nets (13), Beach seines (28) • 5 federally-listed species – Endangered (shortnose sturgeon) – Threatened (Atlantic sturgeon) – Species of Concern (blueback herring, alewife, and rainbow smelt) • 4 species of recreational importance – largemouth and striped bass, pumpkinseed, bluefish • 3 species with commercial fisheries – Atlantic herring, winter flounder, red hake

Introduction Methods Results Conclusions Future Work Summary

• Fish abundance, richness and diversity – Lowest in areas with significant salinity mixing – Greatest in areas with less tidal influence • Diadromous fish not observed – brook trout, sea lamprey and Atlantic salmon* • Comparison to Wells Reserve sampling and (Kiraly et al.,2014)

Introduction Methods Results Conclusions Future Work Comparison to other estuaries • Since 2007, (60) species have been observed in the SRE and Bay – (33) – Kennebec Point (27) – (24) – Wells Harbor (24) – (10) – Penobscot River (35) – (22) – (25) – (24) (Orrniger et al. 2005; Lazzari et al. 1996; Dionne et al. 2006; Ayvazian et al. 1992; Kiraly et al 2014 Lazzari 2002; Lazzari and Tupper 2002; Lazzari et al. 2003)

Introduction Methods Results Conclusions Future Work Future Work

• Continue to collect abundance data – Correlation with freshwater discharge and time from peak high tide • Create a static food web model – Mass-balance approach – Goal: Determine role of diadromous fish as predators and prey

Introduction Methods Results Conclusions Future Work Thank you!

• Sulikowski Lab – Brenda Rudnicky, Julia Reynolds, Ashleigh Novak • This research was conducted as part of the Sustainability Solutions Initiative, supported by National Science Foundation award EPS-0904155 to Maine EPSCoR at the University of Maine

NOAA Section 6 Special License 2013-48-03 Questions? Comments? Suggestions?

Introduction Methods Preliminary Results Conclusions Future Work River Herring Counts

88% decline

7,994

Empty Rivers The Decline of River Herring - A Report of the Herring Alliance Source: ASMFC River Herring Compliance Reports.