Discussion

We hypothesize that buzzards are taking advantage of the mating season of the crayfish when they are more visible, when the water level is a little bit lower, since the cameras where active the whole year and we only recorded this behaviour during this period. Crayfishes may suppose an important energy source during this part of the year, when the young buzzards are flying, since we detected the consumption of this crustacean by Eurasian otters (Lutra lutra ) and American mink (Neogale vison ), (that consume them almost year-round) but especially by red fox (Vulpes vulpes ) that overlapped the consumption period with buzzards (Figure 4).

Conclusion

We describe a new food source and foraging behaviour by a generalist raptor, the common buzzard (Buteo buteo ), contributing to the knowledge of the prey spectrum this species is capable of prey upon in its distribution range.

Figure captions

Figure 1: Study area in Western Iberia (A), in Salamanca province white line (B) and location of the camera trap in the middle of a riparian forest close to the Tormes river (C).

Figure 2: A) Foraging behaviour observed, with the common buzzard patrolling the riverbank looking for prey, including American crayfishes. B) Successful catch of an American crayfish.

Figure 3: Full predation sequence, where the buzzard captures the crayfish in the water and moves to a log to eat it.

Figure 4: American mink (A) and red fox (B) catching crayfishes during the same period as the buzzards.

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Funding Information

None

Conflict of Interest statement

The authors declare no conflict of interest.

Data Availability statement.

All data are contained within this manuscript and its associated tables.

Acknowledgements

To all the people that, at some point, helped with fieldwork during the main study. In memoriam Daniel Saldaña, “Saldi”, who would have loved to know about this behaviour.

Figures

Figure 1