MONICET: The Azores whale watching contribution to cetacean monitoring

The Azores islands have been historically linked to cetaceans, becoming an example of a successful transition from whaling whale watching. Twenty-eight cetacean species sighted in these waters, making the archipelago one most recognised and dolphin watching destinations worldwide. business is well-established region, operates four nine year-round or seasonally provides excellent opportunity collect long term information on distribution abundance affordable way. Continuous monitoring indeed essential establish baseline knowledge evaluate response potential natural anthropogenic impacts. Opportunistic data greatly complement traditional dedicated surveys, providing additional support for appropriate management plans. MONICET platform has running continuously since 2009 as collaborative instrument collect, store, organise disseminate voluntarily collected by companies Azores. In period covered this dataset (2009-2020), 11 provided where takes place. contains more than 37,000 sightings 25 (22 cetaceans three turtles). This manuscript presents first long-term occurrence openly available We explain methodology used collection address biases limitations inherent opportunistic nature maximise its usability external users.