by Bob Fisher
This report was sent to us from Bob Fisher, the chief scientist who is overseeing this project. This report was received on Sept. 23, 1996.
1) Introduction
This project started somewhat precipitously; as a result, the planning that would normally precede such an exercise was considerably curtailed. All tasks not directly involved with collection of baseline data, construction of habitat modules and settlement collectors and their deployment were left to be dealt with as time permitted. All basic tasks were completed and the majority of baseline data collected in August and early September. There are a number of startup tasks remaining to be done, and that - as well as the need to keep this committee informed - is the reason for this meeting. It is necessary for us to agree on the tasks remaining to be completed for startup to be successful. Under the circumstances, I am sure that there were things forgotten in the field with the haste with which this project got underway and I am relying to a great extent on input from this meeting to determine where additional data is required. Over the next 1 - 1.5 weeks I will be finalizing the work plan for the coming field visit to ensure that sampling meets project requirements, that the data is of high quality and that as much data (including possible support for other programs) as possible is collected; advice tendered at this meeting will be incorporated into this work plan.
2) Scope of Work:
includes:
* -Consultation with artificial habitat and lobster ecology researcherson the eastern seaboard and in the U. K. -Pre-startup steering committee meeting to clarify objectives and set schedules.
* -Planning and acquisition of materials.
* -Training of personnel on site and establishment of a sampling and construction timetable.
* -Deployment of thermographs.
* -Start of meteorological and hydrographic monitoring.
* -An extensive survey to identify most suitable bottom. * -Plankton tows were to determine presence of lobster stage II-IV larvae.
* -Suction dredge samples to define bottom structure and biota.
* -Choosing of study sites.
* -Site typification (biological and physical) of both experimental sites and their comparison sites.
* -Video and still camera monitoring of study sites.
* -Deployment of habitat modules.
* -Deployment of settlement collectors.
Tasks which were accomplished either in whole or in part are asterisked. The hard deadline for deployments was the first week in September, as settlement has commenced by then.
3) Site Descriptions:
Two sites were selected, one with bedrock substrate and the other with a flat sand bottom; Ramea Run and Old Ramea Harbor, respectively. Both sites are within 15 minutes by boat from the Town of Ramea, facilitating future field work. Both sites are adjacent to good lobster areas but are , themselves, completely unsuitable as lobster habitat (see appended map).
(Note: the map was not included in the original reciept of materials, contact Bob Fisher directly if you need this information)
The Ramea Run site consists of fractured sedimentary bedrock. This is still packed in place tightly enough to preclude the use of cracks/crevices by any lobster developmental stage. The bottom topography is somewhat uneven, as the rock layers lie almost vertically. Several boulders on the site made it necessary to place habitat modules in a less regular arrangement than on the sand-bottom site. The site is sheltered to the north by Ramea Island, to the south by Southwest Island, to the east by Great Island and somewhat to the west by Columbier and several sunkers. Deployment depth was 15-20' below MLW as this is the depth noted as being best settled by post-larvae in the literature. Occasional crabs (Cancer), whelk and numerous urchins were noted on the site, the latter being removed to provide a better opportunity for settling organisms. Numerous shrimp < 3 cm. TL were also noted. Most of the immediate area around the experimental site is poor lobster bottom, but there is good lobster bottom within 50 meters.
The Old Ramea Harbor site consists of a flat, medium to coarse sand bottom, also at a depth of 15-20' below MLW. Urchins were only present on small rock outcroppings, the other macrofauna comprising quahogs, crabs (Cancer), hermit crabs, sand dollars, Lunatia, juvenile flatfish and sculpins. Adjacent to the artificial habitat area is a 10-15' wide band of fallen rocks along the shore which is known good lobster habitat. A diving transect run along this area noted 8 lobster of commercial or near-commercial size over a distance of 70'. The site has an excellent combination of rapid water turnover and full shelter; it is `workable' in any weather.
A sample refuge area was not selected, although there are several possible ones. Since the lobster season had finished before project startup, this task can be carried out any time before the start of the 1997 lobster season. On reexamination, it is possible that the site noted in Old Ramea Harbor will be the site selected for this. This would simplify sampling by concentrating 3 of 5 sampling locations in Old Ramea Harbor.
4) Tasks Accomplished:
All sampling carried out is shown on the appended map as are habitat sites. Tasks accomplished include:
-Lobster habitat research workshop attendance: was attended in May as part of phase I of the present project. It was held by DFO, St. Andrew's and gave the opportunity for travelling through the northern New England States to discuss the project with some U. S. researchers. Suction dredge sampling methodology was confirmed and the construction and deployment of the settlement collectors ascertained through discussion with Dr. Bob Steneck of the Darling Marine Laboratory.
-Deployment of 2 thermographs: these were emplaced at 3 meters and 7 meters depth on a common anchor in the deepest part of Old Ramea Harbor. -Personnel training: this was considerably reduced because of time constraints. It consisted primarily of personal construction of the first few settlement collectors and continual overseeing of the first 2 pours of concrete for the habitat modules. At startup there were 2 half-day consultation/information sessions including the showing of an informational video on the construction and deployment of habitat modules. Overseeing was unnecessary after the first week. Logistic constraints became the main obstacle to rapid construction after this. -Construction of 140 habitat modules: was carried out at the rate of 11 per day because the full complement of 20 moulds was not available until the end of the period (we were notified that there would be a 4-5 week turn-around time for receipt of moulds from ReefBall Inc. Several of the 2 smallest sizes cast were left onshore at the end of the project, both because they had not cured sufficiently to be safely deployed; this has also provided several display samples for other groups interested in the technology.
-Construction of 30 settlement collectors: was both more expensive and time- consuming than had been anticipated. In the end, construction was limited more by the nature of its own rapidity than by any other factor. With work being carried out so rapidly, it was difficult to determine when the funds allocated to a specific portion of the project had run out; we opted, in light of the nearly doubled cost of collectors, to be conservative in the number constructed to avoid cost over-runs -Survey of suitable bottom: experimental sites selected: at project startup, a major phytoplankton bloom was underway, reducing visibility to < 2 m. This made diving observation necessary for preliminary selection and slowed down the process considerably. Early site examinations carried out by boat with a glass-bottom bucket for viewing bottom topography in April were made possible by the extreme water clarity at the time;visibility was > 10 m. -Plankton tows: were carried out at different locations about the islands, at varying distances offshore and under a variety of wind and light conditions. 44 tows were performed without any lobster larvae being found. -Video and still photographic record of activities: was done on the surface and underwater using a Sony Handycam in a waterproof housing and a 35 mm. Nikonos. -Benthic dredge sampling: was carried out in alternating fashion (3 days each) with the plankton tows. The outriggers used for tows were removed for diving as they interfered with diving operations. 95 samples were collected and examined for the presence of lobster larvae/juveniles. None were found. -Habitat module deployment at two locations: was completed by a combination of carrying out the smaller units by boat and towing the buoyed larger ones (Bay Balls) to the sites and deflating the Polyform buoy flotation. Larger units were lowered by rope as they lost buoyancy to reduce the chance of breakage. Brick rubble was placed on site directly from the boat. Final module positioning and filling with rubble was carried out by divers. -Deployment of settlement collectors: was done in groups of 5 - 0.5 m2 units per location. Locations chosen were in 15-20' of water and in a range of exposures from somewhat exposed to fully sheltered. A total of 30 units were deployed; locations are noted on the appended map
5) Methodology:
Benthic Dredge Sampling - was carried out using a 4" diameter, 2 meter long, air operated suction dredge attached to a surface air supply. 15 - 0.5 m2 samples were taken to a depth of 10 cm. where sediment permitted at each location sampled to provide for an estimation of sampling accuracy. Samples were filtered on location through scallop spat collector bags attached to the outflow (1 bag per sample) which were changed after each individual sample and brought to the surface by the standby diver. Samples were examined in detail onshore, primarily for larval/juvenile lobster and also for benthic infauna. As no lobster have been found this way to date, the results obtained thus far constitute a a semi- quantitative estimation of community structure and size.The fact that highly mobile benthic species including shrimp and Ulvaria were taken regularly indicates that, had lobsters been present, they would form part of the sample. All samples have been formalin preserved for future reference after a preliminary examination for lobster and site-typical organisms.
Plankton Tows - were made using an 18' fiberglass tow vessel equiped with bow-braced outriggers to provide for sampling unobstructed by vessel-induced water turbulence. A 1 meter, 700 micron mesh plankton net was used; this was attached to a rectangular, buoyed net frame designed to sample the top 40 cm. of the water column. Standard tows were for 10 minutes and were taken at varying distances offshore, in various locations, under various lighting and wind conditions. Although numerous crab larvae and some juvenile lumpfish were found in nearshore samples, no lobster larvae were found. As sampling was underway by the second week in August, there must have been larvae present in the water column; one can only attribute their absence in samples to the extreme patchiness of their distribution and the variability of winds during sampling, the latter probably causing larval dispersion. These samples were also formalin preserved but, since they are whole samples, can be used quantitatively.
6) Remaining to Be Done:
(during October revisit) -continuation to phase II b of the project, which focuses on ongoing sampling; involves continuation of funding for researcher. This is number one of the 3 main items of business for this meeting -completion of biological and physical sampling on experimental sites: The next field sampling will take place in October and provides an opportunity to ensure sampling to an acceptable level of accuracy. Deciding what remains to be collected is the second business item.(tentative list appended: October Sampling Task List) -Retrieval of settlement collectors and count of post-larvae: self-explanatory. -establishment of protocols for ongoing monitoring/sampling during absence of research biologist: this is the third main business item to be dealt with.( tentative list appended: October Sampling Task List) -start of collection of existing environmental data: for project background and to address DFO Habitat Branch's requirement for collection of traditional ecological knowledge(TEK). This will be addressed separately with representatives of DFO Habitat Branch before the October field trip. It is not an integral part of the study - it is meant to provide a background to the actual study. The refereed literature portion of this work is proceeding apace,as can be seen from the appended bibliography which has doubled in size from the time of proposal submission. Those references which have not yet been procured will be acquired by the end of the calendar year.
7) Miscellaneous:
Expressions of interest have been received from two other Canadian groups starting habitat enhancement projects using the same type of habitat modules as we have deployed in Ramea. A group in B. C. has raised $350,000 toward a total project cost of $800,000 to build an `artificial reef'. Another group in New Brunswick which is working with Michel Comeau of DFO to build a similar artificial habitat in their area. During the first field study period, the latter group sent 2 observers to Ramea to dive on and observe module deployment and construction techniques. They anticipate startup of their project in 1997. To date, the use of these modules, which have a proven track record in a variety of locations - primarily in the U. S. A., in Ramea is a first not only for Newfoundland but for Canada.
Bernard St. Marie, also of DFO (Gulf Region) has expressed interest in obtaining larval/juvenile samples for incorporation into their sampling program which has been curtailed to the point of there not being any sampling possible in the Newfoundland region except through courtesy from the present project. His group is carrying out studies on lobster bioenergetics which will help to fill in gaps in the knowledge of lobster early life history.
I will be soliciting advice from the following on sampling methodologies and directions via e-mail before the October sampling period: Dr. Peter Lawton(DFO St. Andrews) Dr. Dan Sheehy(Industrial Economic, Inc., Boston) Dr. Stanley Cobb(University of Rhode Island) Dr. Bob Steneck (Darling Marine Laboratory, Maine) Dr. Morgan Goodlad(North Atlantic Fisheries College, Shetlands) Dr. John Wickins(MAFF, U. K.)