A cetacean survey campaign was performed around São Miguel Island (Azores) by Anacaona Sailing boat (GREC) from May 8th to May 17th and from July 4th to August 1st of 2014. The team conducted a total of 18 days of effort around the island. A total of 9 species were sighted during the survey: common dolphin (Delphinus delphis), atlantic spotted dolphin (Stenella frontalis), bottlenose dolphin (Tursiops trucnatus), stripped dolphin (Stenella coeruleoalba), risso’s dolphin (Grampus griseus), sperm whale (Physter macrocephalus), fin whale (Balaenoptera physalus), false killer whale (Pseudorca crassidens) and Blainville beaked whale (Mesoplodon densirostris). The common dolphin together with the Atlantic spotted dolphin were the most sighted species. Some differences in the distribution between the species can be appreciated in the corrected effort maps. Acoustic data is currently under study.info:eu-repo/semantics/publishedVersio

Azevedo, José M. N.

Fernandez, Marc

Gannier, Alexandre

Repositório da Universidade dos Açores

	CIRN/GREC	2014	Campaign	report	Marc	Fernández	Morrón1,	Alexandre	Gannier2	&	José	M.N.	Azevedo1		 1. CIIMAR/CIMAR	-	Interdisciplinary	Centre	of	Marine	and	Environmental	Research,	University	of	Porto	&	CIRN,	Department	of	Biology,	University	of	Azores	2. Groupe	de	Recherché	sur	les	Cétacés	Summary		A	cetacean	survey	campaign	was	performed	around	São	Miguel	Island	(Azores)	by	Anacaona	Sailing	boat	(GREC)	from	May	8th	to	May	17th	and	from	July	4th	to	August	1st	of	2014.	The	 team	conducted	a	 total	of	18	days	of	effort	around	 the	 island.	A	total	 of	 9	 species	 were	 sighted	 during	 the	 survey:	 common	 dolphin	 (Delphinus	delphis),	atlantic	spotted	dolphin	(Stenella	frontalis),	bottlenose	dolphin	(Tursiops	trucnatus),	 stripped	 dolphin	 (Stenella	 coeruleoalba),	 risso’s	 dolphin	 (Grampus	griseus),	sperm	whale	(Physter	macrocephalus),	fin	whale	(Balaenoptera	physalus),	false	killer	whale	(Pseudorca	crassidens)	and	Blainville	beaked	whale	(Mesoplodon	densirostris).	 	 The	 common	 dolphin	 together	 with	 the	 Atlantic	 spotted	 dolphin	were	 the	most	 sighted	 species.	 Some	differences	 in	 the	distribution	between	 the	species	can	be	appreciated	in	the	corrected	effort	maps.	Acoustic	data	is	currently	under	study.			INTRODUCTION		The	 Groupe	 de	 Rercherche	 sur	 les	 Cétaces	 (GREC)	 is	 a	 French	 NGO	 based	 in	Antibes.	 It	 is	 composed	 for	 twenty	 effective	 members,	 having	 as	 president	Alexandre	Gannier.		The	association	seeks	to	provide	scientific	documentation	for	cetacean	populations	management	and	conservation.	The	GREC	is	a	member	of	the	France	Nature	Environment,	official	partner	of	ACCOBAMS	and	scientific	partner	of	PELAGOS	sanctuary.			The	 Centro	 de	 Investigação	 dos	 Recursos	 Naturais	 (CIRN)	 is	 a	 research	 center	based	 in	 the	 Biology	Department	 of	 the	University	 of	 the	Azores.	 It	 has	 as	main	goals	 multidisciplinary	 research	 in	 Biotechnology,	 Biodiversiy	 and	 Biomedical	Sciences.			As	 a	 result	 of	 collaboration	 between	 GREC	 and	 CIRN	 a	 survey	 campaign	 was	performed	during	May	and	 July	of	2014,	around	São	Miguel	 Island,	Azores.	 	This	campaign	was	 included	 in	 the	 framework	 of	 the	 Phd	 Thesis	 of	Marc	 Fernández:	“Habitat	 suitability	 of	 oceanic	 cetaceans:	 Comparing	 presence	 only	 and	presence/absence	modelling”.			Aims		 - To	collect	a	Presence/Absence	dataset	of	cetacean	around	São	Miguel	to	be	compared	with	opportunistic	data	- To	acquire	high	quality	audio	recordings		- To	collect	photos	to	be	included	in	the	MONICET	Photo-Id	catalogue		METHODS		The	11.9	meters	sailing	boat	Anacaona	was	used	as	survey	platform.	A	minimum	of	3	 and	maximum	 of	 5	 observers	were	 used	 for	 cetacean	 detection.	 Speed	 varied	from	3	to	6	knots	with	a	mean	of	4	knots.	All	survey	data	was	introduced	into	the	on-board	 monitoring	 system	 SMAC	 (Système	 de	 Monitoring	 Acoustique	 des	Cétacés).	During	sampling	GPS	was	recorded	every	5	minutes	and	environmental	conditions	 (atmosphere	 and	 sea)	 checked	 and	 entered	 every	 15-20	 minutes.	During	observations	GPS	was	recorded	every	2	minutes.	Due	to	visibility	and	navigability	issues,	effort	was	restricted	to	days	with	Beaufort	<4,	 steady	wind.	More	exactly,	wind	speed	 in	 the	 lower	part	of	Beaufort	4	 range	(11-13	 knots)	were	 often	 compatible	with	 the	 survey,	 when	 the	 upper	 range	 of	Beaufort	4	did	not	allow	the	continuation	of	survey.	For	the	same	reason,	survey	feasibility	 was	 limited	 to	 moderate	 swell:	 swell	 height	 above	 1	 meter	 usually	imposed	limitations	to	the	boat	tracks.	The	survey	spatial	strategy	was	constrained	by	the	availability	of	ports,	and	the	sea	conditions.	The	survey	area	around	Sao	Miguel	was	divided	in	survey	blocks,	both	inshore	and	offshore,	and	survey	blocks	were	accessed	in	relation	to	the	weather	conditions.	The	 survey	 aim	was	 to	 sample	 equally	 the	6	 southern	 survey	blocks,	and	to	survey	at	least	once	the	eastern	and	western	island	tips,	and	northern	area.	A	 random	zig-zag	 sample	was	defined	 in	every	block,	before	 starting	 the	 survey.	Pre-defined	tracks	were	strictly	followed,	or	adapted	to	wind	and	swell	conditions	prevailing	on	the	field.	In	both	cases,	the	survey	tracks	obeyed	to	the	randomness	condition	 necessary	 to	 deliver	 un-biased	 presence/absence	 effort	 and	 sighting	data.	An	acoustic	array	system	was	towed	continuously	during	survey	transects,	feeding	the	 monitoring	 system.	 The	 acoustic	 array	 was	 a	 dual	 stereo	 system	(manufactured	by	Ecologic	Ltd,	UK),	which	was	 employed	 in	 a	wide	band	mode:	with	 a	 96-kHz	 sampling	 rate	 and	 a	 high-pass	 filtering,	 the	 useful	 band	 during	surveys	was	0.2-48	kHz.	This	acoustic	band	was	effective	to	detect	any	odontocetes	in	 the	 Açores	 area,	 including	 physeterids,	 delphinids,	 ziphiids,	 as	 well	 as	 the	medium-sized	 balenopterids	 (i.e.	 excluding	 blue	 and	 fin	 whales).	 Various	 SMAC	software	 options	 enabled	 to	 increase	 the	 acoustic	 survey	 efficiency:	 filtering-denoising,	automatic	triggering…	Every	15-20	minutes	a	human	 listening	was	done	 in	order	 to	record	data	on	 the	acoustic	 environment	 (presence	 of	 cetaceans,	 noise	 level	 and	 nature)	 and	 any	acoustic	 event.	 A	 recording	 was	 done	 whenever	 useful.	 In	 relation	 with	 the	available	crew	on-board,	a	continuous	listening	was	eventually	performed.	The	 periodic	 listening	 will	 be	 used	 to	 provide	 an	 acoustic	 mapping	 of	 cetacean	presence,	 independent	 of	 visual	 contact.	 However,	 the	 classification	 of	 cetacean	acoustic	signals	will	be	limited	to	four	coarse	taxon	level:	sperm	whale,	delphinids,	ziphiids,	other.	During	cetacean	observations,	recordings	were	performed	routinely	whenever	sea	conditions	 permitted.	 Recordings	 were	 of	 variable	 duration,	 with	 full	 species	identification	 in	 relation	 to	 the	 visual	 observation	 in	 progress.	 A	 precise	 and	unambiguous	 signal	 classification	 could	 not	 be	 given	 for	 mixed-species	observations.	The	visually	documented	recordings	will	be	used	 to	provide	new	 information	on	species	acoustic	identification	and	classification,	especially	for	delphinids.	RESULTS			The	present	survey	is	an	addition	to	the	present	cetacean	knowledge	of	the	Azores.	Some	 studies	 have	 been	 conducted	 previously,	 however	 the	 basic	 effort	 was	always	done	around	the	Pico	Island	and	Faial	Island.	From	the	28	species	reported	for	the	Azores	we	found	at	least	9	during	the	18	days	that	the	survey	lasted.			A	total	of	18	survey	days	were	performed,	corresponding	to	144.8	hours	and	1234	km	(Table	1).		 											Tab1.	Detailed	effort	for	the	2014	survey.			 Time	(hours)	 Distance	(km)	Effort	 127.21	 1102.5	Off-effort	 17.59	 131.4		As	the	main	port	was	located	in	Ponta	Delgada	(South	Coast	of	São	Miguel	Island),	most	of	the	effort	was	realized	in	the	South	Coast	(Fig.1).		However	it	is	important	to	notice	that	other	areas	located	at	the	West	were	also	relatively	well	sampled.																				A	total	of	9	different	species	were	sighted,	in	a	total	of	128	sightings.	Most	common	sighted	species	was	the	Common	dolphin	followed	by	the	Atlantic	spotted	dolphin	(Table	2).			Table	2.	Species	sighted	during	the	survey	and	mean	group	size.				Sightings	were	distributed	around	the	entire	island,	clustering	in	highest	effort	area	(Fig.	2).								Species	 Sightings	 Mean	group	size	 	Min/Max	group	size		Delphinus	delphis	(Dd)	 68	 28.36	 	 2-200	 	Stenella	frontalis	(Sf)	 26	 32.28	 	 7-100	 	Physeter	macrocephalus	(Pm)	 13	 5.50	 	 1-12	 	Tursiops	truncatus	(Tt)	 10	 20.90	 	 2-45	 	Balaenoptera	physalus	(Bp)	 4	 3.5	 	 1-6	 	Grampus	griseus	(Gg)	 2	 3.5	 	 3-4	 	Pseudorca	crassidens	(Pc)	 2	 4.5	 	 4-5	 	Stenella	coeruleoalba	(Sc)	 2	 16.5	 	 3-30	 	Mesoplodon	densirostris	(Md)	 1	 3	 	 3	 	Unidentified	Small	delphinids		 14	 -	 	 -	 	Fig.1:	Sampling	effort	(m)	of	2014	survey	around	São	Miguel	Island,	Azores.	Grid	size	of	2km.			Richness	per	unit	of	effort	results	show	how	the	East	and	West	part	of	the	island		together	with	the	North	shore	have	the	highest	values	of	cetacean	species	(fig.	3).						The	Abundance	Per	Unit	of	Effort	of	the	species	encountered	showed	some	differentiations	according	to	characteristics	of	each	species	(Fig.	4)		Fig.	2.	Tracks	and	sightings	from	the	2014	survey	Fig	3.	:	Richness	per	unit	of	effort	(km)	for	2014	survey.	Acoustic	Results		The	2014	scientific	survey	program	around	Sao	Miguel	comprises	two	phases:	(1)	spring	survey	in	May,	(2)	summer	survey	from	6th	July	to	1st	August.	A	total	of	172	recordings	were	obtained	during	13	days	of	acoustic	survey	(Table	3).	From	10th	May	to	17th	May,	22	recordings	were	obtained,	mostly	of	common	dolphins	(Dd),	and	five	of	sperm	whales	(Pm).	Total	duration	of	these	recordings	is	approximately	70	minutes.	From	4th	July	to	1st	August,	150	recordings	were	obtained,	with	a	total	duration	of	about	11	hours.	Among	these	files,	40	are	not	of	good	quality	and	will	probably	not	be	used	for	analysis.	 		Table	3:	Description	of	acoustic	recordings.	Date	 Number	 Species	10/05/2014	 7	 Dd	11/05/2014	 3	 Dd	12/05/2014	 6	 Dd	17/05/2014	 6	 Pm,	Dd	04/07/2014	 5	 Pm	06/07/2014	 25	 Pm,	Sf,	Dd	07/07/2014	 16	 Pm,	Dd,	Sf,	Tt	08/07/2014	 23	 Md,	Gg,	Sf,	Dd	14/07/2014	 8	 Pc,	Pm,	Sf	15/07/2014	 21	 Pc,	Sf,	Dd	23/07/2014	 28	 Pm	28/07/2014	 6	 Dd,	Sf	01/08/2014	 18	 Pm		During	 the	 summer	 survey,	 we	 recorded	 sounds	 in	 the	 presence	 of	 six	 species	(sperm	 whale,	 Blainville's	 beaked	 whale,	 false	 killer	 whale,	 Risso's,	 bottlenose,	common	and	spotted	dolphins),	 although	signal	 level	might	be	very	 low	 in	 some	cases	(Mesoplodon	spp).	Some	recordings	were	made	to	document	boat	noises,	or	ambient	noise.	A	 complementary	 recording	 set	 with	 80	 recordings	 was	 obtained	 while	 the	sailboat	was	on	cruise	in	the	Central	group	between	3	and	13	August.	From	these	data,	a	further	20	recordings	of	sperm	whales	can	be	used	for	analysis.	Sounds	are	now	being	listened	in	order	to	document	the	files,	a	preliminary	stage	before	 focused	 processing.	 However,	 presently	 there	 are	 two	 focused	 analyses	starting:	 (1)	 perform	 contour	 analysis	 in	 order	 to	 quantify	 the	 discrimination	 of	the	two	most	common	dolphins	species	(common	and	Atlantic	spotted	dolphins),	(2)	describe	the	sperm	whale	pulse	repertoire	beyond	the	simple	 foraging	clicks.	Both	analyses	are	now	being	conducted	on	a	pooled	data	set	with	2013	and	2014	recordings	off	Sao	Miguel.	DISCUSSION		The	 campaign	 realized	 in	 summer	 2014	 covered	 mostly	 the	 South	 part	 of	 São	Miguel	Island.	The	west	and	east	point	of	the	island	were	visited	at	least	two	times.		Due	 to	 the	difficulties	associated	with	weather	conditions	 it	was	only	possible	 to	realize	one	full	day	of	sampling	along	the	north	shore	of	the	island.			The	high	number	of	cetaceans	found	at	the	East	and	West	point	could	indicate	that	some	oceanographic	feature	might	be	related	with	their	distribution.	At	the	north	we	 found	 several	 groups	 of	 sperms	 whales,	 which	 suggests	 that	 the	 area	 in	question	might	be	an	important	area	for	this	species.		Putting	 together	 the	 elevate	 number	 of	 sightings	 and	 recordings	 of	 Delphinus	delphis	 and	Stenella	frontalis	 indicates	 how	 these	 are	 the	most	 abundant	 species	for	the	study	area	during	summer	months.	Compared	to	2103	no	mixed	groups	of	both	species	were	found,	and	in	general	groups	were	smaller.	Only	few	recordings	of	active	 feeding	associate	with	seabirds	were	 found,	 in	general	 this	year	 feeding	events	were	smaller	in	size.		Common	dolphin		Common	dolphins	were	found	all	over	the	area.	However	a	clear	pattern	towards	coastal	areas	can	be	observed.	This	might	be	due	to	some	depth	related	issues,	or	maybe	 related	 to	 the	 concentration	 of	 more	 productive	 areas	 near	 the	 shore	(mass-island	effect).		Atlantic	spotted	dolphin		Less	abundant	than	common	dolphins,	this	species	have	more	sightings	during	mid	to	 end	of	 July.	 Sightings	were	 found	more	 spread	 in	 all	 the	 area;	 generally	more	sightings	were	made	 far	 from	shore.	The	biggest	groups	were	 found	at	 the	West	point	of	the	island.		Bottlenose	dolphin		This	year	no	clear	pattern	was	observed	 for	 this	species.	They	occurred	 in	many	places,	however	there	is	a	slight	pattern	in	the	APUE	toward	the	West	part	of	the	island.				Sperm	whale		Sperm	whales	were	sighted	in	3	main	different	spots.	They	were	observed	at	the	East,	the	North	and	offshore	on	the	centre	of	the	island.	Most	of	the	observations	were	done	in	the	East	part	of	the	 island,	towards	the	East	point.	However	Sperm	whales	were	also	found	frequently	at	12-14	miles	outside	of	Ponta	Delgada.			Regarding	 to	 the	 North	 shore	 we	 encountered	 several	 groups.	 Taking	 into	consideration	 that	 this	 area	 was	 sampled	 only	 once,	 this	 could	 indicate	 that	 it	might	be	an	important	part	or	their	habitat.	Most	of	the	animals	encountered	were	on	feeding	behaviour,	however	we	also	found	some	interesting	social	events.		Fin	whales	We	 found	 Fin	Whales	 during	 the	 May	 campaign.	 Sightings	 were	 mostly	 located	close	to	the	coastline	within	relatively	small	groups.	Risso’s	dolphin		This	species	was	sighted	only	two	times	in	small	groups	in	an	offshore	area	outside	Ponta	Delgada.			Stripped	dolphin		We	had	very	few	sightings	of	this	species,	mostly	on	the	East	side	of	the	island.	No	mixed	groups	observed.			False	killer	whales		We	encountered	this	species	in	two	occasions	and	always	on	the	West	side	of	the	island.	 The	 groups	 encountered	 were	 small,	 with	 an	 animal	 with	 a	 spinal	deformation.	Chasing	behaviour	for	feeding	purposes	was	observed	once.	Beaked	Whales		A	 good	 encounter	 with	 beaked	 whales	 allowed	 us	 to	 identify	 a	 group	 of	 2	individuals	of	Mesoplodon	densirostris.	The	animals	were	sighted	at	12-14	miles	off	Ponta	Delgada.										

CIRN/GREC 2014 Campaign report

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