Speaker: Len Thomas (CREEM)
SAMBAH is a 5-year EU-funded project to estimate the abundance of the Baltic Sea subpopulation of harbour porpoise. The population has been drastically reduced over past decades and is now so small that conventional visual survey methods are ineffective due to small sample sizes; hence a passive acoustic survey was designed and implemented, involving around 300 fixed sensors deployed for 2 years. This makes it by far the largest designed passive acoustic density survey in the world to date (accounting for missing data, around 450 years of acoustic data were collected.) The project is a collaboration involving scientists from 9 of the Baltic states, plus CREEM – we designed the survey and performed some of the statistical analysis of resulting data. In this talk I will describe the survey and analyses performed. Results have been released at the level of abundance by region and season, but there is room for refinement, so I’ll be interested to hear any suggestions from the audience.