western rock lobster research simon de lestang jason how matt pember wrl technical team &...
TRANSCRIPT
Western Rock Lobster Research
Simon de Lestang
Jason How
Matt Pember
WRL Technical Team
&
Industry
WRL Research
• Whales
• Puerulus settlement Juveniles
• Deep water settlement– Mesh Pots– Deep water collector
• Tagging project
• Aging project
• Elemental
• Sea Lion Depredation
?
?
Entanglements per season
• Mainly commercial
Entanglements
Entanglements per season
• Reduction in entanglements
• Gear modifications introduced
• Could also be a change in overlap between fishing and whale migration
Whale Movements
Fishing Practices0-9
10-19
20-29
30-39
40+
May Jun
Jul Oct
• Possible change in whale migration– Offshore – anecdotal– Early – entanglements | whale watching
• Minimal change in fishing effort– May & June same as last year– July-Oct reduction (impact of gear mods?)
• Appear gear mods partially responsible for reduction in entanglements
Evaluate 2014 Modifications
• Same gear mods for 2015– Whale ‘zone’ (<20 m depth)– 15 increase to 18 fathoms
2015 Gear Modifications
Spatial Data• Improved information on where and when
whales are located
• Inform management (more tailored)
Spatial Data
• Develop spatial model for humpbacks off WA coast
• Only one data input• App and satellite
tracking data
Satellite Tracking
Whale Surveyors
• Trip back to port• Start & End• July and September
Settlement & Juveniles• Low settlement period
• Change in timing
Settlement
Puerulus to Juveniles• Kackers
– Dongara (7 Mile) – & Lancelin
• Meshed Pots
Meshed Pots
Meshed Pots
Meshed Pots26
37
32
29
21
16
2015.162
• Developed in Tasmania
• Modified for WRL
• Trialed along-side traditional gear
• Next - run off commercial vessel
Deep Water Collector
FRDC Tagging Project
• Validate the stock assessment model and inform quota setting decisions
• New baselines for lobster biomass and exploitation rates.
• Migration, growth and mortality estimates
• Implications of increased high grading
86mm CL non-setose female white 394km in 2.6 months (5.1km/day)
126mm CL ovigerous female1km in 18 years (112mm in 1996)
Recaptures
Tag Releases
11000 lobsters already tagged (20000+ total)
Released in pulses (2/6)
6 main areas (inc BB)
Success of the entire project hinges on reporting
of tag recaptures.
200+ reported by industry
Estimates of reporting rates are required
Releases
46 Fishers (107 WRL)
5 Fishers (7 WRL)
Reporting Rate
Recaptures
REPORTINGCongratulations to winners!
Thank you to all making returns
Success of the entire project hinges on reporting of tag recaptures.
We don’t care how we get them.•Use the App!•Write in CDR! •Use Tag Cards!•Use the Web!•SMS Details!•Email or ring us!
• Tag number
• Date
• Location
Release Survival
Release Damage
Big Bank
Aging• Currently from tagging /
length frequency• Southern Cross University
– Crustacean scientists around Australia
• Direct age of lobster– How old– Age at maturity– Growth rates through fishery
• Currently– Stained lobsters– Sectioning for aging
27 mm ♀
124 mm ♂
Elemental my dear Watson
• Given known locations
• Blind test (random)
• Successful location id
• Expand the project [funding ?]
• Combine with aging– Locations through life cycle
• Answer questions– Origin of Big Bank lobsters as juvenile– Degree of cross zone movement
Elemental my dear Watson
Sea Lion Depredation
Sea Lion Depredation
Conclusions
• Variety of programs• Whales; Sea Lions; Tagging; Elemental; Deep-water
settlement; Aging
• Industry is often an official partner in the research [Whales & Tagging]
• Need industry assistance in getting data
• All for the betterment of the industry