Foreword to Conventional Tagging Section
Jeremy R. McKenzie
In the 20 years since the last tagging symposium (Parker et al 1990), despite the remarkable development of acoustic and satellite tags, the long-standing or “conventional” tags (including passive integrated transponder (PIT), coded wire (CWT), anchor, and Visible Implant (VI) tags) remain crucial for fisheries management and research and still far outnumber all other types of tags deployed.
Fish tagging studies can be broken down into three broad categories: assessing the effectiveness of enhancement and mitigation programs; determining migration patterns, habitat use, and stock separation; estimating growth, survival, and population size. The use of conventional tags under each of these categories is represented by one or more papers in this section. These papers also exemplify some key advances in conventional tagging technologies, specifically in: the bulk application of tags (Vander Haegen et al.); tag coding and information content (Vander Haegen et al., Marvin, van den Broek et al.); tag detection and real-time processing of recovery data (Marvin, Achord et al., Baker and Smith, Lipsky et al.). These advances now enable the provision of management advice which was difficult, albeit impossible, to attain back in 1988 with conventional tagging technologies.
As remarkable as tagging technological developments have been in the last 20 years, it is important not to lose sight of the fact that technical advancement is born out of management requirement. It is therefore fitting we begin this section with a management paper (Bronte et al.) describing an enhancement program for the Laurentian Great Lakes intended to restore native fish stocks. The necessities of the Pacific Northwest and Great Lakes salmon programs underlay the development of the AutoFish™ CWT system (Vander Haegen et al.), the most technological advanced automated fish tagging system currently available.
The final paper in this section by Weitkamp is a spatial analysis of many years of cumulative Pacific Northwest salmon tagging data. Although interesting in itself, the Weitkamp paper serves to illustrate how long time-series tagging data can provide management insight beyond the original purpose or intent of collection. Weikamp’s paper is food for thought in the context that, in each passing year, millions of conventional tags are seeded into world fisheries.