Reproductive Ecology of Atka Mackerel, Pleurogrammus monopterygius, in Alaska, Lauth, R.R.

These data are part of a study detailed in Lauth et al. (2006; North Pacific Research Board Final Report 417;
http://doc.nprb.org/web/04_prjs/f0417_final_report.pdf). Two manusripts are also in the works: 1) a manuscript by Lauth et al. entitled
"Geographic distribution, depth range, and description of Atka mackerel (Pleurogrammus monopterygius) nesting habitat in Alaska" is in press
with the Alaska Fisheries Research Bulletin, and 2) a manuscript by Lauth et al. entitled "Reproductive cycle of Atka mackerel (Pleurogrammus
monopterygius) in Alaska" is in review with the US Fishery Bulletin.
This study provides new information on the reproductive cycle of Atka mackerel (Pleurogrammus monopterygius) in Alaska waters. Results
from this study are a first step toward investigating complex ecological mechanisms linking environmental factors and recruitment processes
of Atka mackerel. Research provided from this study will be very useful to stock assessment biologists and managers for improving the Atka
mackerel stock assessment and developing more prudent harvest management strategies. Both fieldwork and laboratory studies were conducted.
One-hundred and nineteen underwater video camera tows across Alaska were made for locating and describing the general spawning and nesting
habitat, and to determine the geographic distribution and depth range of spawning and nesting sites. Camera tow sampling was conducted at
various dates between June and October 2004 using National Marine Fisheries Service (NMFS) charters F/V Sea Storm, F/V Gladiator, F/V Seafisher,
and the U.S. Fish and Wildlife R/V Tîglâx. The study area included the continental shelf regions of the Aleutian archipelago and the central
Gulf of Alaska. Field collections of egg masses from nesting sites were aged to determine the temporality of spawning and nesting in Alaska.
To parameterize the incubation model for aging egg masses, it was necessary to do laboratory experiments at the Alaska SeaLife Center to
determine how Atka mackerel incubation time varied at selected water temperatures. Analyses of the spatio-temporal reproductive state by
reproductive stage, size and maturity was done using gonads and length frequency data collected from cruises at Seguam pass, Tanaga pass,
and the Amchitka Island Area in 2002 and 2003 during NMFS Atka mackerel tag recovery cruises. This same data was also used to investigate
the annual and spatial variation in the female maturity schedule. Data on spawning coloration and egg mass abundance was from a 2004 NMFS
Atka mackerel tag recovery cruise. All the data from this study is in an access database consisting of: 1) camera tow tracklines by vessel;
2) camera tow depth and temperatures collected with a SeaBird SBE 39; 3) camera tow headers; 4) camera tow notes file for sites where nest
guarding males were observed; 5) ages of egg masses relative to a developmental series conducted at 6°C; 6) header file for hauls with egg
mass collections; 7) SeaBird SBE 39 depth and temperature log of trawl hauls where egg masses were collected; 8) Egg mass abundance data at
trawl locations from the 2004 NMFS Atka mackerel tag recovery cruise; 9) Trawl hauls with nesting males from the 2004 NMFS Atka mackerel tag
recovery cruise, and 9) histological analysis of gonads collected from cruises at Seguam pass, Tanaga pass, and the Amchitka Island Area in
2002 and 2003. These datasets were archived as part of the North Pacific Research Board legacy project recovery effort undertaken by Axiom Data Science and NPRB in 2025. The goal of the recovery effort was to assess the NPRB-funded data projects from 2002 to 2014 and archive final data packages that were ready for publication to increase long-term accessibility and discoverability. Data packages were archived as is given limited funding and resources.