Message from the VP Marine Science
Rockfish Conservation Areas (RCAs) were established in BC in 2004 to protect and conserve inshore rockfish. At the same time, Aquarium divers started scuba dive census work on inshore rockfishes inside and outside RCAs in Howe Sound. The initial purpose of this project was to provide firm data for final selections of RCAs in 2006. Known sites were investigated to provide input to RCA selection that was underway in 2004-2006. A second goal, undertaken during 2006, with funding from the University of California Davis, was to determine which local features best predict rockfish habitat. To that end, videotaped surveys were analyzed in 2006, and previously unstudied areas were surveyed in 2006, inside and outside the final RCA selections. DFO provided the Aquarium with the intended final designations for 2007 during April of 2006, in order to facilitate this study. We now have an independent evaluation, for Howe Sound, of the rockfish habitat model that was used by DFO in RCA selection for the entire BC coast.
This project occupied a great deal of the Howe Sound team’s time during 2006, but routine monitoring of prawns and glass sponges was not neglected. Connections between diverse projects emerged as a result of this broad field presence. It is doubtful whether we could have in any way predicted the connections that became evident. Because of the rockfish surveys we were led to a new appreciation of the extent of dispersal of prawns. We also came to realize that cloud sponge reefs in Howe Sound, like eel grass beds in Howe Sound, simply are not as significant as nursery habitat for rockfish as has been reported from other geographic areas. The likelihood is that young rockfish cue in to the most suitable nursery habitat that they encounter in a region. For Howe Sound that means that baby copper rockfish live around a type of kelp that occurs very widely in Howe Sound, and baby quillbacks live in cobble fields in deeper water. In Puget Sound, where eel grass is abundant in the relatively shallow water, young rockfish use eelgrass as nursery habitat, and cloud sponges are nursery for quillbacks around Texada Island. Different rules for different regions.
Dr. Jeff Marliave
May, 2007
2006 Fish Research Projects
International Internship
September 2006 marked the start of a six-month internship for French fisheries student Marc Sicard. Rather than to conduct a research thesis, French students work at various placement jobs internationally, then write a report on their experiences. While here, Marc participated in field diving projects such as the rockfish abundance surveys as well as working on larval descriptions of copper rockfish that had been reared in the lab earlier in 2006. Marc conducted microscopic examination of body measures and pigment cell counts from a preserved series of development stage of copper rockfish, toward the comparative description of china, copper and quillback rockfish larvae.
Rockfish Winter Hiding
Added to the ongoing rockfish abundance counts was a further category of whether the observed fish were found “inside” or “outside” of their chosen rock-pile habitat. Those found out in the open (where they would be visible on a videotape transect) were scored as being “outside” whereas those hiding under rocks were scored as being “inside.” Interestingly, sites where rockfish have been observed to be overwhelmingly “outside” during summer months were entirely “inside” during winter months. These results were observed for copper rockfish in shallow, shoreline rock piles. The results indicate that the fish are not migrating into deep water for the winter period, but instead hide deep in the safety of the rock pile.
Acoustically Tagged Rockfish Project
The last full year of effort in this monitoring of black rockfish transplanted to Point Atkinson was in 2006. The data from seven tagged black rockfish were recorded from five receiver downloads, spanning 17 months from December 2004 to January 2007. These data (a total of 1,651,771 detections) are being plotted in a 24-hour clock format, with activity patterns of the rockfish shown corresponding to the time of day at which they occurred. The tagged black rockfish have exhibited complete home-site fidelity and relatively small home ranges. The data also demonstrate that the fish move around their home reef area in social groupings. They do not show the kind of daily rhythm that is familiar to higher animals, in that evidence for hiding in rock piles tends to follow one pattern for a number of days, then a different pattern persists for a brief period, without any long-term, principal time of day for rest periods.
Fish Research Lab Welcomes A New Employee
In September 2006, a new employee was hired to work in the Fish Research lab. Zhen Hong Luo grew up on a koi farm run by his father in Guangzhow (Canton City), Southern China and has a strong academic and practical background in larval fish rearing and animal husbandry in both China and Singapore.
2006 LEMS Study
The 13th annual lingcod egg mass survey concluded with a total of 81 dives and was again strongly supported by volunteer divers throughout BC. The results indicated that lingcod are starting to recover around greater Vancouver thanks to a total ban on recreational fishing. However, despite this encouraging news the results also showed that lingcod abundance and age structure on offshore reefs and islands in Howe Sound were declining. This finding, combined with the observation of boats with poachers in these areas, led to the conclusion that poaching had shifted “offshore” in Howe Sound into areas where fishing regulations may be harder to enforce.
Howe Sound Sponge Monitoring
Aquarium staff continued to monitor tagged glass sponges in Howe Sound as well as film and conduct taxonomic surveys of a newly found cloud sponge reef or “bioherm,” much larger than other previously observed examples nearby.
Juvenile Spot Prawn Abundance Monitoring
Aquarium staff continued with their SCUBA counts of juvenile spot prawns in their nursery habitat under large bladed algae. In conjunction with new survey areas for Rockfish Conservation Areas, it was realized that juvenile prawn abundance can vary quite widely between areas that are relatively close, for example, Pam Rocks versus Finisterre Islet. This observation suggests the possibility that prawn larvae may resist drifting with currents away from their hatching site, a prospect that would affect management considerations for prawn fisheries. Prawns are managed in relatively large areas, as with all of Howe Sound.
Rockfish Habitat and Biodiversity Survey
Work on this project was completed by Aquarium staff in October 2006 and the data analysis was underway during 2006. A complete taxonomic survey of all algae and animal life at each of the randomly chosen sites was recorded together with bottom type, and will be used to test the predictive model for rockfish abundance used by DFO in their establishment of Rockfish Conservation Areas. Rockfish in Howe Sound were relatively abundant both inside the predicted areas of abundance and outside them.
Research Lab Successfully Rears Copper Rockfish
Aquarium staff successfully reared copper rockfish larvae through to the juvenile stage. The larvae were conceived in the Aquarium’s Pacific Canada exhibit, then the two female parents were transferred to the research laboratory to give birth in a two-tonne tank for larval rearing. The experience has provided valuable information on the dietary requirements of the larvae, as well as other new rearing techniques that will be employed with future rockfish births. New conservation concerns for inshore rockfish have resulted in strict limits on collecting permits for display purposes, in line with new restrictions on sport and commercial catches for these long-lived species.
Eighth Generation of Tubesnouts
Line-breeding of tubesnouts continued with the eighth generation born in the summer of 2006. Despite repeated inbreeding, this species still shows no sign of deleterious genes and the fish appear morphologically identical to their wild cousins. This strong resistance to inbreeding depression is thought to result from their life-history characteristic of no planktonic drift as larvae. For animals which regularly have opportunities to mate with siblings, the species typically has eliminated bad gene combinations through survival of the fittest. Other species bred at the Aquarium, such as the sailfin sculpin, for which larval drift dispersal is very extensive, tend to suffer from inbreeding depression within a few generations.
“Windows On Research” Display Sheds Light On Research Projects
Two new display tanks designed for larval fishes are in the newly opened Canaccord Discovery Gallery. Combined with improved public interpretation abilities in Aquaquest – the Marilyn Blusson Learning Centre, these display tanks give the public a glimpse into current fish research projects, both in the lab and in the field. Larval fish rearing conducted in the lab is highlighted in the display tanks whereas interpretive delivery combined with movie clips highlight field work such as the Lingcod Egg Mass and Rockfish Abundance surveys.
Larval Fish Rearing
The research lab continued with its rearing of larval grunt sculpins, hybrid blenny-eels, rock pricklebacks, and painted greenlings. Juveniles of all these species were produced, except in the case of the hybrid eels. This marked the third time that larvae spawned by adults of a hybridization between two species of cockscomb pricklebacks had been reared in the Aquarium lab without successful development to the juvenile stage. The possibility exists that the hybrids are capable of spawning but that their offspring cannot survive through larval development. The original hybridization was allowed to test whether the rare, deep-water species was indeed a true, biological species.
Dietary Immunostimulation of Pink Salmon
Experimental trials were conducted in an attempt to determine the efficacy of introducing a mushroom immunostimulant into test diets and its subsequent effect on sea lice infection resistance in pink salmon. Unfortunately, adequate infection rates were not achieved and precluded any significant difference in resistance between the experimental and control groups. The experiment is to be repeated in 2007 with modified techniques employed to ensure a higher level of sea lice infection. It has repeatedly occurred in scientific tests that pink salmon are less susceptible to sea lice infection, compared to chum salmon. The sea lice infectious stages were provided by Dr. Kevin Butterworth of the UBC/DFO West Vancouver Laboratory.
Blood Analysis Conducted On Chum Salmon Fed Experimental Diet
Dr. Shannon Balfry of DFO’s West Vancouver Laboratory extracted blood samples from chum salmon that had been reared in two groups for a year at the Aquarium (2005-2006). The fish were fed either an experimental immunostimulant or a regular control diet. Shannon is still in the process of analyzing the samples, but preliminary results indicate that fish receiving the experimental diet additive had significantly increased haematocrits. The behaviour and appearance of the salmon fed the immunostimulant was different as well. This experimentation relates to long experience with live foods versus prepared foods. Frozen storage tends to affect fish feeds in ways that suppress the immune capability of the fish. One solution would be to add immunostimulants to the diet, since live food is often not practical.
HSRCG 2006 Fish Research Staff
Dr. Jeff Marliave, VP Marine Science
Paul Malcolm, Research Diver/Writer (partial support from Howe Sound Group)
Donna Gibbs, Research Diver/Taxonomist (partial support from Howe Sound Group)
Conor McCracken, UBC Student Technician*
Zhen Hong Luo, Laboratory Technician
Justin Lisaingo, SFU Student Technician (full support from Howe Sound Group)
Marc Sicard, Diver (French graduate student intern)
*seconded to Paul Malcolm’s position during Paul’s leave of absence (May 2006)
Financial Statement
Funds Received
Carry-Forward . . . . . . . . . . . . . . . . . $ 6,000
Regular Donations . . . . . . . . . . . . . $24,000
Special Donations . . . . . . . . . . . . . . $11,300
SeaDoc Society Grant . . . . . . . . . . . .$27,000
MITACS matching grant . . . . . . . . . $15,000
NSERC IPS matching grant . . . . . . .$15,000
VA Conservation Foundation . . . . . $12,000
Total . . . . . . . . . . . . . . . . . . . . . . . . $110,300
Expenditures
Carry-Forward (SeaDoc) . . . . . . . . . $14,000
MITACS matching funds . . . . . . . . . $15,000
NSERC IPS matching funds . . . . . . . $6,000
SFU Statistics (MITACS, NSERC) . $30,000
Repairs and Equipment . . . . . . . . . . . $11,200
Dive Medicals . . . . . . . . . . . . . . . . . . $ 2,200
Horseshoe Bay Sign . . . . . . . . . . . . . . $ 800
VA Payroll . . . . . . . . . . . . . . . . . . . . .$30,800
Total . . . . . . . . . . . . . . . . . . . . . . . . $110,300
2007 Budget Projections
SFU Statistics . . . . . . . . . . . . . . . . . . $14,000
NSERC IPS match (renewal) . . . . . . $ 6,000
Repairs & Equipment . . . . . . . . . . . $ 4,000
Lingcod Egg Mass Survey . . . . . . . . $ 5,000
Lingcod Egg Mass Survey Report . . . $ 3,000
Prawn Survey . . . . . . . . . . . . . . . . . . . $ 2,000
Sponge Monitoring . . . . . . . . . . . . . . $10,000
Rockfish Surveys . . . . . . . . . . . . . . . . $15,000
Seabed Mapping/Photomurals . . . . . . $10,000
Proposed Budget for 2007 . . . . . . . . .$69,000