Abstract
European Union (EU) legislation requires Member States to monitor the environmental status of European maritime waters and the conservation status of protected species including cetaceans, to assess the impact of anthropogenic activities and the effectiveness of management and conservation actions. Year-round shipboard surveys were conducted between 2007 and 2012 in Madeira archipelago coastal waters, realizing 8713 km of track line (10–24 replicates of each block surveyed) in sea conditions of Beaufort ≤ 4, to study the distribution and abundance of cetaceans. Abundance was estimated using design-based distance sampling methods, whereas distribution was modeled using generalized additive models. Twelve species were recorded, and mean abundance in the study area was estimated for common bottlenose dolphin (623; CV = 0.212), Atlantic-spotted dolphin (985; CV = 0.292), common dolphin (546; CV = 0.280), short-finned pilot whale (120; CV = 0.324), Ziphiidae (31; CV = 0.342), and Balaenopteridae (19; CV = 0.296). These first-surface point estimates of mean abundance and model-predicted distribution for these taxa in Madeira waters provide baseline values for future assessment of their status for the EU Habitats Directive and Marine Framework Strategy Directive. They are also the basis for the creation of a Site of Community Interest for the bottlenose dolphin and an important contribution for the spatial management of whale-watching activities in Madeira.
| Original language | English |
|---|---|
| Article number | e70065 |
| Journal | Marine Mammal Science |
| Volume | 42 |
| Issue number | e70065 |
| Early online date | 6 Sept 2025 |
| DOIs | |
| Publication status | Published - 1 Jan 2026 |
Keywords
- Atlantic spotted dolphin
- bottlenose dolphin
- common dolphin
- generalized additive models
- Habitat Directive
- line transect sampling
- Madeira archipelago
- Marine Framework Strategy Directive
- monitoring
- short-finned pilot whale