Residency and connectivity between Pacific halibut residing in Inshore and Offshore waters: insights from the Salish Sea and Glacier Bay, Alaska

Residency and connectivity between Pacific halibut residing in Inshore and Offshore waters: insights from the Salish Sea and Glacier Bay, Alaska Timothy Loher and Eric Soderlund International Pacific Halibut Commission, Seattle WA Julie Nielsen Kingfisher Marine Research, Juneau AK Andrew Seitz University of Alaska, Fairbanks Photo: Kerri Johannson

The Fish Closely related to Atlantic halibut (Hippoglossus hippoglossus) Photo: Rudolf Svendsen

The Fish Distributed throughout the north Pacific, from northern California into the northern Sea of Japan Al Russia Bering Strait Chukchi Sea Norton Sound Alaska Great Bear L. Great Slave L. Sea of Okhotsk Shirbhov Ridge Bering Sea Bowers Ridge Bristol Bay Gulf of Alaska o 60 N sou o 45 N Sea of Japan North Pacific Ocean o 135 E o 150 E o 165 E 180 o 165 o W 150 o W 135 o W 30 o N Figure 1.1. The North Pacific Ocean and Bering Sea.

The Management Structure Basic elements of management include: Restricting harvests to hook-and-line

The Management Structure Basic elements of management include: Restricting harvests to hook-and-line Harvest limits (quota) set within regional Regulatory Areas

The Management Structure Basic elements of management include: Restricting harvests to hook-and-line Harvest limits (quota) set within regional Regulatory Areas 1

The Management Structure Basic elements of management include: Restricting harvests to hook-and-line Harvest limits (quota) set within regional Regulatory Areas 2 1

The Management Structure Basic elements of management include: Restricting harvests to hook-and-line Harvest limits (quota) set within regional Regulatory Areas 3 2 1

The Management Structure Basic elements of management include: Restricting harvests to hook-and-line Harvest limits (quota) set within regional Regulatory Areas 4 3 2 1

The Management Structure Basic elements of management include: Restricting harvests to hook-and-line Harvest limits (quota) set within regional Regulatory Areas

The Management Structure

The Management Structure Salish Sea

The Salish Sea Image: Seattle P.I. Named for its indigenous people: the Coast Salish Nations Lummi Nooksack Makah Quinault Quileute S Klallam Suquamish Skokomish Swinomish Tulalip

The Salish Sea Image: Seattle P.I. Whose fisheries occur on their Usual and Accustomed Grounds

The Salish Sea Image: Seattle P.I. Whose fisheries occur on their Usual and Accustomed Grounds Lummi Inshore Nooksack (Salish Sea) sector Swinomish S Klallam

The Salish Sea Image: Seattle P.I. Whose fisheries occur on their Usual and Accustomed Grounds Offshore sector Makah Quinault Quileute Lummi Inshore Nooksack (Salish Sea) sector Swinomish S Klallam

The Salish Sea Image: Seattle P.I. This has led to questions to what extent the Pacific halibut harvested by the two sectors are different

The Salish Sea Image: Seattle P.I. This has led to questions to what extent the Pacific halibut harvested by the two sectors are different Based on analyses of otolith microchemistry: {Salish Sea} halibut may belong to a distinct stock that are significantly different from {Washington Coast} halibut. - Gao et al. 2012; Env. Biol. Fish 95:469-479

The Salish Sea Image: Seattle P.I. Experiment conducted in 2014-2015 designed to ask: Do female Pacific halibut remain in the southern Salish yearround, or do they join Offshore spawning groups?

The Salish Sea Image: Seattle P.I. Experiment conducted in 2014-2015 designed to ask: Do female Pacific halibut remain in the southern Salish yearround, or do they join Offshore spawning groups? If Pacific halibut overwinter in the Salish Sea, is there evidence that they spawn there? If they depart, do they return afterwards or remain Offshore?

Pop-up Archival Transmitting (PAT) tags Computerized tag that records light, depth, temperature Tag is darted into the fish, just below the dorsal fin Allows for FOUR relevant analyses

Pop-up Archival Transmitting (PAT) tags 1 - Final locations Tag releases ( pops up ) on a pre-determined date and broadcasts to Argos satellites Tag signal is used to generate a positional fix Yields locations to within 50m: unbiased recovery, no matter where the fish is Graphic: Service ARGOS

Pop-up Archival Transmitting (PAT) tags 2 - At-liberty locations Light data can also be used to estimate at-liberty locations, under ideal conditions Graphic: Tag-a-Giant Foundation

Pop-up Archival Transmitting (PAT) tags 3 - Seasonal depth and temperature changes Depth data can be used to define seasons from the perspective of the fish

Pop-up Archival Transmitting (PAT) tags 4 - Short-period depth = active spawning 1/12 Day 1/14 1/16 1/18 1/20 1/22 1/24 1/26 Short period vertical rises were discovered in archival depth records in 2004 (Seitz et al., Env Biol Fish 73:445-451) 89:30 83:04 93:27 Nigh t 90:27 - Evenly-spaced, very rapid, only in mid-winter, occur 5-8 times and then stop Jul 26 Jul 27 Jul 28 234 m at the peak Jul 29 Jul 30 Jul 31 Off-bottom egg release in a batch spawner 7 minutes up and 24 back down 470 m at base elevation

The Salish Sea Photo: Rich Rosenthal Twelve female Pacific halibut were tagged at five locations Tags programmed to report in two batches - Mid-January (spawning season): n = 4 - Late spring (feeding season): n = 8 ** * * *

The Salish Sea Photo: Rich Rosenthal Twelve female Pacific halibut were tagged at five locations Large fish selected to ensure high probabilities of maturity

The Salish Sea Photo: Rich Rosenthal Call this Results - Part 0 Large fish selected to ensure high probabilities of maturity Except that probably not

Results: tag pop-up locations A Do Salish Pacific halibut join offshore spawning groups? Yes they do: clearly demonstrated by two fish 24 November 15 January

Results: tag pop-up locations A Do Salish Pacific halibut join offshore spawning groups? Yes they do: clearly demonstrated by two fish Fish with biggest ovaries

Results: tag pop-up locations B Do Pacific halibut remain in the Salish Sea year-round? Also yes : apparently so, for four fish

Results: tag pop-up locations B Do Pacific halibut remain in the Salish Sea year-round? Also yes : apparently so, for four fish Fish with secondbiggest ovaries 19 Mar 15 Jan * * * * * 15 Jan 15 Jan

Results: tag pop-up locations B Do Pacific halibut remain in the Salish Sea year-round? Also yes : apparently so, for four fish ** * * *

Results: light-based longitudes C And some appear to be non-spawning transients Evidence of this from 2 fish * * * * * 15 January 8 May

Results: light-based longitudes C And some appear to be non-spawning transients Evidence of this from 2 fish

Results: fishery recovery Image: Lummi Natural Resources D For migrants, do they return or remain offshore?

Results: fishery recovery Image: Lummi Natural Resources D For migrants, do they return or remain offshore? January 2015

Results: fishery recovery Image: Lummi Natural Resources D For migrants, do they return or remain offshore? January 2015 Recaptured: April 2016

Results: tag pop-up locations Image: Lummi Natural Resources D For migrants, do they return or remain offshore? They demonstrate both behaviors June 2015 January 2015 Recaptured: April 2016

Results: high-resolution depth data E Any evidence of spawning in the Salish?

Results: high-resolution depth data E Any evidence of spawning in the Salish? No

Results: high-resolution depth data E Any evidence of spawning in the Salish? No* * NOTING: this analysis was only possible for 4 fish; but, did include an individual with large ovaries

The Salish Sea Image: Seattle P.I. In summary: There is clear connectivity between Salish Sea and Offshore Pacific halibut spawning stock However, Salish Sea demographics and behavior appear to display some unique features: - - - - Emigrant spawners depart fairly late in the season There is evidence of year-round residency of likely-mature fish, but without evidence of spawning while in the Salish Sea Large but apparently-immature females seem relatively abundant There is evidence of seasonal connectivity that does not display what we understand of the typical spawning circuit

Glacier Bay Image: US National Park Service Also in the eastern Gulf of Alaska, but farther north: Glacier Bay Salish Sea

Glacier Bay Image: US National Park Service Also in the eastern Gulf of Alaska, but farther north: A system of deep, narrow fjords Established as a Marine Protected Area (MPA) in 1998

Glacier Bay Image: US National Park Service Experiment* conducted in 2013-2014: Using a combination of pop-up satellite and acoustic tags; the latter monitored via mobile tracking with fish double-tagged *Published in Nielsen et al. (2017), ICES J. Mar Sci. 74: 2059-2068

Glacier Bay Image: US National Park Service Experiment* conducted in 2013-2014: Using a combination of pop-up satellite and acoustic tags; the latter monitored via mobile tracking with fish double-tagged Primary focus was to examine connectivity between Park Waters and outside, in the context of MPA utility *Published in Nielsen et al. (2017), ICES J. Mar Sci. 74: 2059-2068

Glacier Bay Image: US National Park Service Fish (n=25) were tagged and tracked in the mainstem of the Bay: Net Squared: Fig 1 *Published in Nielsen et al. (2017), ICES J. Mar Sci. 74: 2059-2068

Glacier Bay Image: US National Park Service Recall the sizes tagged in the Salish Sea

Glacier Bay Image: US National Park Service Recall the sizes tagged in the Salish Sea These were even larger

Glacier Bay Image: US National Park Service In addition to tag locations (from tracking and tag pop-up), oceanographic data provided an indication of movement Resident:

Glacier Bay Image: US National Park Service In addition to tag locations (from tracking and tag pop-up), oceanographic data provided an indication of movement Resident: Migrant:

Glacier Bay Image: US National Park Service allowing for each fish s residency/migration characteristics to be tracked over time: (Published in Nielsen et al. (2017), ICES J. Mar Sci. 74: 2059-2068)

Glacier Bay Image: US National Park Service allowing for each fish s residency/migration characteristics to be tracked over time: (Published in Nielsen et al. (2017), ICES J. Mar Sci. 74: 2059-2068) Photo: David Bryan

Glacier Bay Image: US National Park Service allowing for each fish s residency/migration characteristics to be tracked over time:

Glacier Bay Image: US National Park Service Summary results: High rate of residency - ~76%

Glacier Bay Image: US National Park Service Summary results: High rate of residency - ~76% But with clear evidence of connectivity with offshore: - Transient departurereturn = 16%

Glacier Bay Image: US National Park Service Summary results: High rate of residency - ~76% But with clear evidence of connectivity with offshore: - - Transient departurereturn = 16% Potential exportemigration = 8%

Glacier Bay Image: US National Park Service Summary results: High rate of residency - ~76% But with clear evidence of connectivity with offshore: - - Additionally: - No evidence of spawning within the Bay - Transient departurereturn = 16% Potential exportemigration = 8% Emigration occurs relatively late in the season

Both inshore systems Image: Seattle P.I. Image: US National Park Service Connectivity spans a range of resident an migratory forms - Partial migration

Both inshore systems Image: Seattle P.I. Image: US National Park Service Connectivity spans a range of resident an migratory forms - Partial migration A tendency towards late spawning?

Both inshore systems Image: Seattle P.I. Image: US National Park Service Connectivity spans a range of resident an migratory forms - Partial migration A tendency towards late spawning? Many large fish, that appear immature or non-migratory - - Delayed maturation or rapid growth? The result of one-way emigration in combination with the above?

Both inshore systems Image: Seattle P.I. Image: US National Park Service Is this a common feature of the eastern fjordlands

Both inshore systems Image: Seattle P.I. Image: US National Park Service Is this a common feature of the eastern fjordlands, relative to offshore and regions with less-complex geomorphology? 4 3 2 1