Monchong”“Monchong”

Home , Pomfret

ProgressProgress inin studiesstudies onon thethe lifelife historyhistory andand ecologyecology ofof “monchong”“monchong”

Michael P. Seki, Donald R. Hawn, and Robert Nishimoto National Marine Fisheries Service, NOAA Pacific Islands Fisheries Science Center 2570 Dole Street Honolulu, HI 96822-2396 Taractichthys steindachneri NorthNorth PacificPacific BramidsBramids

Taractes rubescens

¾ Two largest of eleven known pelagic “Bramid” species in North Pacific (most Taractes asper “forage-fishes”) Eumegistus illustris ¾ Attain ca. 80 cm TL & 13.5 kg (~30 lbs)

Brama orcini Brama japonica Pterycombus petersii WhatWhat areare monchong?monchong?

¾Commercially prized “exotic” fish – particularly in the Hawaii restaurant trade ¾Most monchong landed by Hawaii-based longliners and treated as incidental catch not “bycatch” WhatWhat areare monchong?monchong?

Taractichthys Sickle pomfret ¾ E. illustris alsoalso takentaken byby steindachneri bottomfishersbottomfishers (and(and seamountseamount handlinershandliners)) ¾ Unfortunately,Unfortunately, forfor mostmost (if(if notnot all)all) existingexisting data,data, nono distinctiondistinction betweenbetween speciesspecies mademade –– i.e.,i.e., treatedtreated asas aa speciesspecies complexcomplex

Eumegistus illustris Lustrous pomfret Background:Background: UnitedUnited FishingFishing AgencyAgency landings,landings, 19871987--20022002

Annual landings (lbs) 18K - 300K

Avg. individual fish wt. (lbs) 13.0-17.7 lbs

Mean price (per lb) $ 1.35 - 1.96

Annual ex-vessel revenue $35K - $630K

(Data courtesy R. Ito, NMFS PIFSC) MOTIVATIONMOTIVATION

¾ Study funded by the PFRP beginning Sept 2001 … continues today ¾ Because not a target species, VERY limited information available regarding the life history and ecology of these resources ¾ A “signature species” in the “deep ecosystem” of tuna longlining (with bigeye tuna and opah) ¾ Fascinating ecological subjects but quite a challenge to study ResultsResults fromfrom thethe studystudy provide:provide:

¾ newnew andand muchmuch neededneeded informationinformation thatthat willwill helphelp refinerefine aa precautionaryprecautionary referencereference pointpoint andand inputinput intointo ecosystemecosystem--basedbased fisheryfishery managementmanagement policypolicy ResultsResults fromfrom thethe studystudy provide:provide:

¾ newnew andand muchmuch neededneeded informationinformation thatthat willwill helphelp refinerefine aa precautionaryprecautionary referencereference pointpoint andand inputinput intointo ecosystemecosystem--basedbased fisheryfishery managementmanagement policypolicy ¾ insightsinsights intointo factorsfactors thatthat enhanceenhance andand reducereduce thethe incidentalincidental taketake ofof thesethese speciesspecies PrimaryPrimary ObjectiveObjective

Simply … to investigate and define some of the fundamental life history and ecological characteristics of the “monchong” resources in the North Pacific. SpecificSpecific projectproject goalsgoals ……

¾ ComprehensiveComprehensive seasonalseasonal andand wherewhere possible,possible, interannualinterannual biometricbiometric summariessummaries andand relationshipsrelationships (e.g.,(e.g., lengthlength--weightweight frequencies,frequencies, sexsex ratio,ratio, etc)etc) ¾ DeterminationDetermination ofof reproductivereproductive parametersparameters (incl.(incl. sizesize andand ageage atat maturity,maturity, fecundity,fecundity, spawningspawning season,season, GSI)GSI) ¾ FirstFirst cutcut ageage andand growthgrowth estimationsestimations SpecificSpecific projectproject goalsgoals ……

1.1. ConductConduct aa comprehensivecomprehensive shoreshore-- basedbased biologicalbiological samplingsampling programprogram United Fishing Agency (UFA); i.e., fish auction: ¾ Catch and size composition 9For monchong – species differentiation ¾ Special effort to link UFA metrics with biological sampling MonchongMonchong SpeciesSpecies SpecificSpecific UFAUFA SamplingSampling NMFS-UFA monitoring, 1984-2000 Species No. (%) Lbs. (%) E. illustris 1,020 (2.1%) 14,526 (2.0%) T. steindachneri 46,786 (97.9%) 717,174 (98.0%) **recent confirmation of mixed catch on set – mixed schools (?)

19 7000 Average weight

18 6000

17 5000 ) sh s b 16 4000 t (l h t g

i 15 3000 e W Number of fi 14 2000

13 1000

12 0 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 Year 80

Taractichthys steindachneri Buyers/Dealers 70

¾ Length, Weight, Sex 60 th (cm)

eng 50 ¾ Morphometrics L Female (n = 136) 40 Male (n = 131) L = 34.04W 0.31 ¾ Biological samples for (cm) (kg) 30 02468101214 reproduction and ageing Weight (kg) AgeAge && Growth,Growth, TaractichthysTaractichthys steindachneristeindachneri

¾ For T. steindachneri, n = 183 ¾ Using microincrements on postrostrum and/or rostrum of sagittal otolith ¾ IF microincrements are daily, monchong appear to grow rapidly in 1st year; ages of 42-49 cm FL fish ranged from ~12 – 13.5 months. ¾ Microincrement counts also suggests spring spawning. ¾ Oldest fish estimated at about 8 yrs. (based on annuli counts) ¾ Juveniles from stomach contents (e.g, swordfish rats) now being employed PrinciplePrinciple projectproject activities:activities:

1.1. ConductConduct comprehensivecomprehensive shoreshore--basedbased biologicalbiological samplingsampling programprogram 2.2. PerformPerform anan analysisanalysis ofof spatialspatial distributiondistribution patterns,patterns, preferredpreferred habitat,habitat, faunalfaunal associations,associations, andand trophictrophic relationshipsrelationships SpatialSpatial distributiondistribution patterns,patterns, preferredpreferred habitat,habitat, faunalfaunal associationsassociations andand trophictrophic relationshipsrelationships

March Monchong catches with Topex altimetry

1999 2000 ¾ Analysis and merging of industry (fishery), research, and environmental 2001 2002 datasets 2001 2002 MonchongMonchong catchescatches typicallytypically peakpeak inin springspring

¾ 99.29% taken in “deep” tuna sets; 6 5 Longline CPUE 2001 ¾ no evidence of surface ) 2000 set 1999

er 4 p 1998 occupation ( UE ¾ spring catches 3

~ related to spawning? nchong CP o M 1 ~ GSI (♀s): 3.35 – 5.11 "Deep sets only"

0 ¾ fall catches 123456789101112 ~ GSI (♀s): <2.25 Month ¾ CaptureCapture depthdepth && temptemp informationinformation collectedcollected fromfrom Temp-Depth vesselsvessels ofof opportunity:opportunity: Recorders

F/V Tucana: 87 monchong / 16 opah in 13 Hook timers sets; 30 fish in TDR instrumented sections – including 13 monchong & 1 opah; 2 opah & 1 monchong tagged w/PATs 0 Set 4, basket 2 F/V Sea Pearl: 21 monchong / 18 opah in 13 100

sets; breakdown in instrumented sections yet 200 to be determined 300 ) “Monchong (10) in instrumented sessions taken 400

in depths ranging from 174-415 m; mean eters 500 capture depth = 299.9 m (M=313 m) … in (m 0

comparison, bigeye tuna caught in depths pth Set 9, basket 2 ranging from 233-384 m; mean = 285.5 m … De 100 T. rubescens (telecon): 406-415 m 200

300 ¾ DietDiet studiesstudies 400

“monchong” 500 5 1015202530 Time (hours) ProjectProject status:status:

¾ Progressing:Progressing: somesome facetsfacets ofof studystudy fasterfaster thanthan othersothers ¾ Data/sampleData/sample collectionscollections andand analysesanalyses continue;continue; addedadded summersummer ’03’03 samplingsampling triptrip