Occurrence of fin whale (Balaenoptera physalus) in the Azores archipelago: assessment on its migration behavior and first photo-ID catalogue of the area.
Violi B.
[email protected]
Biagio Violi1,2,3 & Rui Peres dos Santos1
1. FUTURISMO, Portas do Mar, Ponta Delgada, Azores, Portugal 2. Department of Earth, Environment & Life Sciences (DISTAV), Genoa University, Genoa, GE, Italy
DA08
3. MENKAB: il respiro del mare NGO, Savona, SV, Italy
Why do fin whales across Azores waters?
DATASET (from 2012 to 2017) Obtained trough whale watching activities: 488 sightings 933 individuals 845 images taken for photo-ID GPS and behavioral data
What do they do?
Azores
Does whale watching activity affect their normal behavior? How many are they?
Figure 1. Map of Azores archipelago
Behavior around Azores waters
60
Response to the boat presence 100
50
2012
40
2013 2014
30
2015
20
2016 2017
10 0
Percent of observed behavior (%)
Percent of observed behavior (%)
RESULTS 1: Observed behavior and response to the boat presence 2012
80
2013 2014
60
2015 40
2016 2017
20 0
FO
TS
TA
M
R
TF
SO BR
Behaviors
LB
SP
FL
H
B
NI
A
I
Behaviors
E
Figure 2. Histograms showing data recorded in different years from 2012 to 2017: main behaviors (on the left) and the whale response to the whale watching boat presence (on the right).
• The main observed behaviors among different years were: (T) travelling 48% and (FO) foraging 29%. • The response to boat presence were largely (I) indifferent 84% and (A) approaching the vessel 11%.
Faial
Faial
Pico
Pico
• Regarding the Sightings information it seems to exist a specific area (south of Pico) for fin whale sightings. • On the analyses of the Encounter Rate, our data show´s that it doesn't exist any specific ground for fin whale observation.
Figure 3. Map of Sighitings and Encouter rate in the study area
RESULTS 2: Photo-ID catalogue Pictures were sorted following quality criteria (from Q1 to Q5) and only images with Q4 and Q5 quality were used, generating a total of 420 photo-ID images. We got: • 214 different identified individuals • 5 individuals rematched between years • 28 days the longest period in which a whale traveled in the same area
Figure 4. Photo-id catalogue : two individuals recaptured in the South waters of Pico island.
Fin whales are quite abundant in spring time during the migration from breeding to feeding grounds [1]. Our results confirm that Azorean waters act as a corridor for fin whales or baleen whales in general, above all for travelling/foraging. This is probably a result of the spring bloom in the area [2] It seems that do not exist a specific feeding ground, before they pursue northward migration. Our data confirm that the whale watching boat presence doesn’t affect the natural behavior of the species. A total of 214 different individuals were identified for the first fin whale Azorean Catalogue. References. [1] Silva, M. A., Prieto, R., Jonsen, I., Baumgartner, M. F., & Santos, R. S. (2013). North Atlantic blue and fin whales suspend their spring migration to forage in middle latitudes: building up energy reserves for the journey?. PLoS One, 8(10). [2] Visser, F., Hartman, K. L., Pierce, G. J., Valavanis, V. D., & Huisman, J. (2011). Timing of migratory baleen whales at the Azores in relation to the North Atlantic spring bloom. Marine Ecology Progress Series, 440, 267-279.
32st Annual Conference, European Cetacean Society 2018, La Spezia, Italy
