Fisheries and Oceans Pêches et Océans Canada Canada Canadian Stock Assessment Secretariat Secrétariat canadien pour l’évaluation des stocks Research Document 99/004 Document de recherche 99/004 Not to be cited without Ne pas citer sans permission of the authors1 autorisation des auteurs1 Striped bass culture in eastern Canada David Cairns Science Branch, Department of Fisheries and Oceans, Box 1236, Charlottetown PEI C1A 7M8 [email protected] Kim Robichaud-LeBlanc Science Branch, Department of Fisheries and Oceans, Halifax, NS B3J 2S7 [email protected] Rodney Bradford Science Branch, Department of Fisheries and Oceans, Halifax, NS B3J 2S7 [email protected] Richard H. Peterson Science Branch, Department of Fisheries and Oceans, St. Andrews, NB E0G 2X0 [email protected] Randy Angus Cardigan Fish Hatchery, AVC Inc., RR3 Cardigan PEI C0A 1G0 [email protected] 1 This series documents the scientific basis for 1 La présente série documente les bases the evaluation of fisheries resources in Canada. scientifiques des évaluations des ressources As such, it addresses the issues of the day in halieutiques du Canada. Elle traite des the time frames required and the documents it problèmes courants selon les échéanciers contains are not intended as definitive dictés. Les documents qu’elle contient ne statements on the subjects addressed but rather doivent pas être considérés comme des as progress reports on ongoing investigations. énoncés définitifs sur les sujets traités, mais plutôt comme des rapports d’étape sur les études en cours. Research documents are produced in the official Les documents de recherche sont publiés dans language in which they are provided to the la langue officielle utilisée dans le manuscrit Secretariat. envoyé au secrétariat. ISSN 1480-4883 Ottawa, 1999 ABSTRACT pour mettre en archives de telles informations pour l'est du Striped bass (Morone saxatilis) culture in eastern Canada est recommandé. Canada began with experimental enhancement and rearing programs in the 1980s. Nineteen facilities have cultured INTRODUCTION striped bass in the region, but only 11 of these continue to The striped bass (Morone saxatilis) presently exists in work with the species. Eight small commercial only two confirmed spawning populations in eastern aquaculture ventures have been initiated in southwestern Canada; one in the southern Gulf of St. Lawrence New Brunswick, mainland Nova Scotia, Cape Breton (Miramichi River) and one in the Bay of Fundy system (the Island, Prince Edward Island, and eastern Quebec. Four of Shubenacadie River and its tributary, the Stewiacke). these operations have ceased bass culture, and the However, striped bass are commonly encountered in a remaining four raise bass at a small scale with limited wide geographic area of the Maritime Provinces due to the commercial sales. The St. Andrews Biological Station has species' highly mobile lifestyle (Bradford et al. 1999a, ended its striped bass program, but research and 1999b). The commercial fishery for striped bass has been development work continues at the Huntsman Marine discontinued because of the small size of remaining Sciences Centre and the Nova Scotia Agricultural College. stocks, but Canadian interest in striped bass aquaculture Pilot culture projects also continue at divested federal has recently intensified, following the development of a hatcheries in Cardigan PEI and Miramichi NB. To date, significant US industry (Harrell 1999). In addition, striped major capital investment, appropriate sites and equipment, bass are considered an attractive sport fish, and hatchery and expert husbandry have not been brought together in a stocking programs may have potential in re-establishing single striped bass venture in eastern Canada. Reliable spawning populations in areas from which they have been information on striped bass transfers and escapes is extirpated, or in enhancing populations in areas where they necessary for development of strains suitable for naturally occur. aquaculture, to evaluate potential alteration of the genetic The genetic lineage of cultured fish is important both to make-up of wild stocks through interbreeding of escapees the culturist and to the conservationist. Comparative and wild fish, and to trace potential routes of disease growth trials of striped bass raised in standardized transmission. It is recommended that a system be conditions have revealed a latitudinal cline in innate growth established to record and archive such information for rates, with northern fish outgrowing those from southern eastern Canada. regions (Conover et al. 1997, Brown et al. 1998, D. Conover pers. comm.; see Appendix 1 for affiliations of personal RESUMÉ communicants). This suggests that Canadian fish, La culture du bar rayé (Morone saxitilis) à l'est du Canada especially those from the northern range limit (the a commencé avec des programmes d’ensemensement et Miramichi), might be particularly suitable for aquaculture d'élevage dans les années 1980. Dix-neuf installations ont operations. In many aquaculture settings, there is a pratiqué l’élevage du bar rayé dans la région, dont possibility of fish escaping, which may lead to the seulement onze continuent de travailler avec l'espèce. Huit introduction of cultured genotypes into the gene pool of projets d'aquaculture ont été mis sur pied dans le sud- local wild fish. ouest du Nouveau-Brunswick, la terre ferme de la Nouvelle- Since the beginning of Canadian striped bass culture Écosse, l'île du Cap Breton, l'île du Prince Édouard, et in the early 1980s, culture has been attempted at l'est du Québec. Quatre de ceux-ci ont cessé la culture du numerous sites in the three Maritime Provinces and bar rayé, tandis que les quatre autres continuent d'élever Quebec. This report 1) documents the history and present le bar à petite échelle et connaissant des ventes limitées. status of striped bass culture operations in eastern La Station biologique de St. Andrews a terminé son Canada, 2) tracks the genetic lineage of transferred fish programme sur bar rayé, mais les travaux de recherche et where possible, and 3) outlines information requirements de développement continuent au Centre des sciences de for the management of striped bass culture in the context la mer Huntsman et au Collège d’Agriculture de la of wild striped bass conservation. Nouvelle-Écosse. Des projets pilots continuent aussi aux écloseries de Cardigan à l’IPÉ, et celui de la Miramichi au STRIPED BASS CULTURE IN EASTERN CANADA N-B, qui appartenaient auparavant au gouvernement fédéral. Jusqu'à date, des investissements majeurs en Rearing practices capitaux, les sites et les équipements appropriés, ainsi The following account of striped bass rearing methods que l'expertise en élevage n'ont pas tous été rassemblés is summarized from Peterson et al. (1996). Striped bass dans un seul projet d'élevage de bar rayé à l'est du collected for broodstock can be maintained on a diet of Canada. De l'information fiable sur les transfères et les pelleted fish food, although fish which are stressed on évasions est nécessaire pour le développement de races capture may be reluctant to take artificial food. Ovarian propices à l'aquaculture, pour une évaluation des development is monitored by removing eggs through a changements potentiels dans le génome des bars catheter. Spawning is induced by hormone injection when sauvages dus aux croisements entre ceux-ci et les bars the eggs reach 0.8 - 1.0 mm in diameter. Eggs are évadés, et pour tracer les routes que peuvent prendre les released by the female and milt is released by the male maladies. L'établissement d'un système pour enregistrer et without stripping. The fertilized eggs are moved to other 2 containers where they hatch in 48-72 hours at 16-18oC. At variation in intrinsic growth rate (Conover et al. 1997, D. 5-10 days post-hatch the yolk sac is depleted and the Conover pers. comm.). larvae are fed Artemia nauplii. An alternative to Artemia In 1991, several hundred juvenile striped bass were feeding is pond rearing, in which larvae are placed in open obtained from eel fishermen in Richibucto, NB. Most were ponds where they forage on zooplancton, particularly used in osmoregulation studies, but six were kept as rotifers. Striped bass in the juvenile stage can be fed prospective broodstock, and reached maturity in 1996. artificial fish food, using the same pellet size as These fish were maintained in a common tank with four fish recommended for juvenile salmon of similar size. Young collected as juveniles from the Kouchibouguac River, NB, striped bass can be raised for grow-out either in tanks, by Bill Hogans of Huntsman. They were spawned together earthen ponds, or in sea cages; all three methods have as “Miramichi” stock. been used in eastern Canada. Salt or brackish water gives Several thousand 5-10 g juveniles were given to superior growth rates to fresh water. Striped bass are Connors Bros. and to Earl Carpenter in the early 1990s for warm-water fish, and warm temperatures (>15oC) are culture at Lake Utopia and Tobique, respectively. However, necessary for rapid growth. temperature and water hardness were unsuitable at these facilities and the bass did not grow well, and were Site accounts destroyed. Several dozen larger juveniles were placed in a This section gives accounts of all the striped bass sea cage with several thousand Atlantic salmon in Beaver culture operations in eastern Canada known to the authors. Harbour. Although they overwintered successfully, they The information comes chiefly from present and former showed poor growth, and were destroyed. facility operators via written reports and (more frequently) In 1994, several hundred juvenile bass of telephone interviews. In most cases site histories, Stewiacke/Shubenacadie origin were sent to including origins and fates of fish, were supplied from Whycocomagh, Cape Breton Island (Loch Bras d'Or memory. Hence there is much unevenness in the level of Salmon Farms).