krillgrowth 93mar 03apr-05may93 Instantaneous growth rate and molting frequency of Antarctic krill from experiments held on board ship at ambient temperatures for short periods. Animal: sex, total length, molt period, telson length of animal and molt if molted Experimental: temperature of seawater, time observed animals for presence ofmolts, dead animals 1) molting frequency (%/day): 100 * number molters/number of experimental animals/duration of experiment in days. the inverse of the molting fequency is the intermolt period in days 2) percent growth per intermolt period (% growth/IMP): 100 * (animal telson - molt telson)/molt telson Eight adult growth experiments from 3 to 29 April and eight larval growth experiments from 21 April to 5 May were conducted. Only krill in good physiological condition were used in IGR experiments, i.e. swimming, no white sections in abdomen. Krill were used from either standard tows or targeted tows. All lively swimming krill were gently placed in a large volume of cold seawater, and then 100 randomly selected krill were gently placed in individual 2-liter (adults) or 500 ml (larvae) vessels in a flowing seawater table at ambient temperature. Temperature was recorded, and animals were checked every 12 hours for molts over the following 4 days. Dead or unhealthy animals were noted. Once an animal molted, both animal and molt were removed from the vessel. The total length of the fresh animal was measured with digital calipers, then molt and animal were preserved together in 10% formalin. The lengths of the telson of the animal and the molt were measured under a binocular microscope back at University of California at Santa Barbara. At the end of the experiment, the total lengths of all non-molters were measured, and the non-molters preserved together. Total length is from the tip of the rostrum to the end of the uropods, not including spines (Standard Length 1, Mauchline 1981). Dead or dying animals were excluded from experimental totals, but their total lengths recorded. Instantaneous growth rate (IGR) experiments were conducted across the grid to observe growth both on and off shore and at the northern and southern area of the sampling region. Larvae were only collected while sampling on the southern stations of this cruise. antarctic krill, growth rates, molting frequency ascii, comma separated variable There are 2 summary files for each study plus individual files for each experiment. 1) adultIGR.details and larvalIGR.details give the details of the experimental checking, with experiment number, initial temperature, local time of checking for periods 1-8, temperature of seawater at time of checking periods 1-8, and number of molters at time of checking periods 1-8. 2) adult IGR.sum and larvalIGR.sum are summaries of results, with experiment number, event number, trawl number, day/month started, local time started, grid location, average temperature (¡C), number of molters, number of animals in experiment, duration of experiment, molting frequency (% per day). 3) in a directory called AIGR are located files containing the length measurements and sexual identification for each experiment: sex (im immature; F female; M male; J/SA juvenile or subadult; MM mature male; MF mature female), animal total length (mm), molt period, animal telson length (mm), molt telson length (mm), comments (dead animals; problems; etc) 4) in a directory called LIGR are located files containing the length measurements and stage identification for each experiment: stage (furcilia 1 to 6), animal total length (mm), molt period, animal telson length (mm), molt telson length (mm), comments (dead animals; problems; etc). ~lter/lterdata krill mac and robin's mac /93mar/* adultIGR.details adultIGR.sum /adultIGR AIGR(experiment number)ev(event number).dat [1-119;2-285;3-354;4-390;5-477;6-527;7-621;8-694] larvalIGR.details larvalIGR.sum /larvalIGR LIGR(experiment number)ev(event number).dat [1-452/454;2-590;3-709;4-717;5-750;6-767;7-773;8-788] Robin M. Ross, Langdon B. Quetin none Robin M. Ross, Langdon B. Quetin Robin M. Ross, Tim Newberger, Treva Coe, Holly Coe, Giovanni Catalano, David Post, Stephen Pryor, Laura Serold The research team on board measured total length and telson lengths of animals and molts live on board during and immediately after the experiment. Carol Wyatt-Evens remeasured telson lengths on the preserved samples. C Wyatt-Evens and C. Tracy Shaw Robin M. Ross, Langdon B. Quetin Langdon B. Quetin AIGR and individual files on experiments submitted 10 Jan 1996. adultIGR.details submitted 24 Dec 1996 adultIGR.sum submitted 24 Dec 1996 IGR experiments with this protocol conducted with Antarctic krill wer reported in: Quetin, L. B. and R. M. Ross. 1991. Behavioral and physiological characteristics of the Antarctic krill, Euphausia superba. Amer. Zool. 31: 49-63. Ross, R. M. and L. B. Quetin. 1991. Ecological physiology of larval euphausiids, Euphausia superba (Euphausiacea. Memoirs of the Queensland Museum 31: 321-333. Initial measurements of telson lengths were made on board by whoever was checking the experiment. Subsequently Carol Wyatt- Evens remeasured all telson lengths in a laboratory setting where accurate measurements under a microscope are easier. Comparison of the results showed that although the average % growth per intermolt period was the same for the two sets of measurements, the variance was decreased when just one person measured all the animals. Measurements on live animals yielded the required precision for total length.

Datafile Form V1.2 for describing a data file.