GULF COAST RESEARCH LABORATORY

703 East Beach Drive

Ocean Springs, MS 39564 USA 

Phone: 228-818-8847 | Fax: 228-818-8848

http://www.scemfis.org

 Page 1 of 3

VIRGINIA INSTITUTE OF MARINE SCIENCE

College of William & Mary, P.O. Box 1346

Gloucester Point, VA 23062 USA

Phone: 804-684-7360 | Fax: 804-684-7537

http://www.scemfis.org

Science & Industry 

Working Together for

Sustainable Fisheries 

- A National Science Foundation Industry/University Cooperative Research Center (I/UCRC)

SUBJECT:	Response	to	BOEM	Request	for	Information on	the	Development	of	a	Long	Term	

Monitoring	Plan	for	Marine	Mammals	in	the	Gulf	of	Mexico;	MMAA	104000

FROM:	Independent	Advisory	Team	on	Marine	Mammal	Assessment (Paula	Moreno,	André

Punt,	John	Brandon, Randall	Reeves), Science	Center for	Marine	Fisheries	(SCeMFiS),	Gulf	

Coast	Research	Laboratory,	University	of	Southern	Mississippi,	703	East	Beach	Drive,	

Ocean	Springs,	MS	39564

DATE:	8	December	2015

The	 Independent	Advisory	Team	(IAT)	was	established	in	early	2014	 to	add	 to efforts by	

others	 (notably	 NOAA	 scientists) to	 address	 uncertainties	 in	 marine	 mammal	 stock	

assessments,	 focusing	initially	 on	 the	Atlantic	 region.	The	 IAT	 has	initiated	a	 project	 that	

will	use	a Management	Strategy	Evaluation	framework	to	test	a	tiered	approach	to	setting	

Potential	 Biological	 Removal	 (PBR) values	 for	 marine	 mammal	 stocks.	 The	 team	 is	 also	

considering	 conducting a	 meta-analysis	 of	 Gulf	 of	 Mexico stock	 assessment	 reports to	

characterize	uncertainties	and	evaluate	the	strengths	and	weaknesses	of	the	methods	that	

have	been	used	to	assess	marine	mammal	stocks	in	the	region.

We	offer	the	following	thoughts	on	various	aspects	of	long-term	monitoring	that	should	be	

considered	 for	 incorporation into	 BOEM’s	 planning	 process for	 long-term	 monitoring of

marine	mammals	in	the	Gulf	of	Mexico.

Baseline	Information:

The	 importance	 of	 having	 reliable	 baseline	 (reference)	 data	 has	 been	 underscored	 by	

recent	events	in	the	Gulf	(notably	the	Deepwater	Horizon	oil	spill) and	this	is	now	widely	

recognized.	Data	obtained	 through	NOAA	stock	assessment	surveys	and	BOEM-sponsored	

programs	such	as	GulfCet during	the	1990s and	the	Sperm	Whale	Seismic	Study	during	the	

early	 2000s provided a	 valuable	 foundation.	 Any	 support	 BOEM	 can	 provide	 to	 enable	

additional	 surveys	 that	 complement,	 supplement,	 and	 extend	 those	 foundational	 data	

would	be	welcome.	Particular	attention	should	be	given	to	(a)	times	or	areas	not	previously	

well	 surveyed (historically,	 offshore	 survey	 coverage	 has	 been	 greater	 than	 coverage	 of	

inner	 shelf	 and	 coastal	 waters,	 bays,	 and	 estuaries)	 or	 not	 surveyed	 for	 a	 long	 time,	 (b)	

species	or	stocks	that	are	defined	as at	risk	(listed	as	threatened	or	endangered under	the	

ESA,	 classified	 as	 strategic under	 the	 MMPA,	 etc.),	 (c)	 populations	 that	 are	 known	 or	
GULF COAST RESEARCH LABORATORY

703 East Beach Drive

Ocean Springs, MS 39564 USA 

Phone: 228-818-8847 | Fax: 228-818-8848

http://www.scemfis.org

 Page 2 of 3

VIRGINIA INSTITUTE OF MARINE SCIENCE

College of William & Mary, P.O. Box 1346

Gloucester Point, VA 23062 USA

Phone: 804-684-7360 | Fax: 804-684-7537

http://www.scemfis.org

Science & Industry 

Working Together for

Sustainable Fisheries 

- A National Science Foundation Industry/University Cooperative Research Center (I/UCRC)

suspected	 to	 be	 discrete	 and	 small	 even	 if	 the	 data	 in	 support	 may	 be limited	 (e.g.	 Gulf	

Bryde’s	whales),	and	 (d)	offshore	cetaceans	 that	are	known	or	suspected	 to	be	especially	

vulnerable	to	noise	exposure	(e.g.	ziphiids,	Risso’s	dolphins).

Bottlenose	Dolphins:

The	 bottlenose	 dolphins is	the	 Gulf’s	 most	 conspicuous,	 frequently	 observed,	 and	 iconic	

cetacean.	It	is also, in	some	ways, the	most	vulnerable	because	some stocks inhabit	nearshore	 and	 inshore	 waters where	 human	 activities	 are	 most	 varied	 and	 intense.	It	 is	 not	

surprising	that	bottlenose	dolphins are	the	cetaceans	most	frequently	involved	in	unusual	

mortality	events,	 one	of	which was	declared	in	 the	Gulf starting	in February	 2010.	Stock	

delineation	 is	 fundamental	 for	 all species	 but	 it	 is	 especially	 challenging	 in	 the	 case	 of	

bottlenose	 dolphins,	 because	 there	 are	 numerous	 stocks	 with	 complex	 connectivity	

patterns	 within	 the	 Gulf.	 Any	 long-term	 monitoring	 program	 should	 include	 a	 strong	

component	 focused	 on	 bottlenose	 dolphins,	 and	 this	 should	 include	 photo-identification	

(for	 abundance	 estimation,	 movement	 analysis,	 social	 connectivity) and	 biopsy sampling

(for	 genetic,	 contaminant, and	 diet	 analyses), health	 assessment,	 and	 habitat	 use	 studies.	

Surveys	and	studies	should cover	the	entire	range	of	stocks	to	ensure	that	valid	inferences	

regarding	 changes	 over	 time	 are	 not	 confounded	 with	 possible	 changes	 in	 distribution.	

Existing	efforts	of	 these	kinds	should	be	continued	or,	where	necessary,	initiated. Results	

should	 make	 it	 possible	 for	 BOEM	 to	 determine	 which	 stocks	 occur	 in	 or	 near	 areas	 of	

active	Oil	and	Gas	(O&G) exploration	or	extraction	activities, and	are	therefore	most	at	risk	

from	the	effects of	such	activities.	

As	 suggested above,	 baseline	 information	 is	 key	 to understanding	the	 impacts of	 human	

activities	on	wildlife	populations. The	occurrence	of	bottlenose	dolphins in	near-shore	and	

inshore	 waters	 has	 spurred	 numerous research	 efforts	 over the	 last	 few	 decades.	 We	

believe	that	BOEM	should	take	advantage	of	this	situation	by:	(a)	identifying	existing longterm	 baseline	 studies,	 (b)	 ensuring	 that	 archived	 data	 are	 prepared	 and	 processed	

following	 current	 technological	 standards	 (e.g.,	 high-resolution	 scanning	 of	 pre-digital	

imagery),	and	(c) ensuring	that	appropriate	analyses	of these	data	sets	are	carried	out.

Cumulative	Impacts:

The	 oil	 and	 gas	 industry,	 as	 well	 as	 its	 regulators	 (BOEM),	 may	 regard	 monitoring	 of	

cetaceans	(and	other	wildlife)	in	areas	other	 than	 those	where	specific	O&G	activities	are	

taking place	 to	 be	 outside	 their	 sphere	 of	 responsibility.	 Although	 cumulative	 (or	

aggregate)	impacts	are	routinely	acknowledged	to	be	a	valid	concern,	the	development	of	
GULF COAST RESEARCH LABORATORY

703 East Beach Drive

Ocean Springs, MS 39564 USA 

Phone: 228-818-8847 | Fax: 228-818-8848

http://www.scemfis.org

 Page 3 of 3

VIRGINIA INSTITUTE OF MARINE SCIENCE

College of William & Mary, P.O. Box 1346

Gloucester Point, VA 23062 USA

Phone: 804-684-7360 | Fax: 804-684-7537

http://www.scemfis.org

Science & Industry 

Working Together for

Sustainable Fisheries 

- A National Science Foundation Industry/University Cooperative Research Center (I/UCRC)

methods	to	characterize,	quantify,	and	assess	such	impacts	is	in	its	infancy.	BOEM	would	be

well	advised	 to	invest	in	cumulative	impact	assessment	in	 two	ways:	(a)	by	ensuring	 that	

relevant	data	are	collected	as	part	of	long-term	monitoring	(including	geo-referenced	data	

on	 human	 activities	 as	 well	 as	 marine	 mammal	 distribution	 and	 abundance)	 and	 (b)	 by	

supporting	developmental	work	on	ways	to	use	those	data	in	cumulative	impact analyses.

Stranding	Networks:

Multiple	lines	and	levels	of	evidence are	often	needed	 to	establish links	between	cases	of	

serious	injury	or mortality	of	marine	mammals	and	specific causal	 factors,	including	O&G	

activities such	 as	 seismic	 surveys.	 Networks	 that	 help	 ensure	 detection,	 necropsy,	 and	

sampling	 of	 stranded	 marine	 mammals	 are	 valuable	 elements	 of	 long-term	 monitoring.	

Oceanographic	modeling	may	enhance	 the	value of	information	obtained	 from	strandings	

by	 allowing	 estimation	 of the	 location	where	 death	 occurred and	 therefore	 aiding	in	 the	

determination	of	the	probable	cause(s)	of	the	mortality.

Risk	Analysis:

Risk	analysis	should	be	used	to	rank	relative	vulnerability	of	different areas,	species,	and	

stocks to	the	effects	of	seismic	surveys.	Such	ranking	can	then	be	employed	to	help	ensure	

appropriate	sampling	strategies,	survey design, survey	techniques,	etc.

Improved	understanding of	marine	mammal distribution and	habitat	use: a step	toward	

accurate	forecasting models:

To	 better	 understand	 the	 dynamics	 of	 marine	 mammal	 distribution	 and	 habitat-use	

patterns	 (including	 relative	 abundance),	 a	 suite	 of	 environmental	 attributes	 that	 include	

“drivers”	(e.g.,	prey)	as	well	as “stressors”	(e.g.	seismic	surveys,	naval	exercises),	should	be	

monitored	 long-term.	 In	 the	 Gulf	 of	 Mexico,	 for	 example,	 foraging	 may	 be	 especially	

intensive	 in	 certain	 areas	 (e.g.,	 associated	 with	 Loop	 Current	 eddies,	 Mississippi	 River	

plume)	and	 seasons	 (e.g.,	in	 relation	 to	prey	migrations). The	 techniques	used	 to	acquire	

such	data	and	their	spatio-temporal	resolution	will	vary.	Ideally,	environmental	attributes	

will	be	monitored	coincident	with	abundance	surveys,	as	well	as	via tagging	devices,	fixed

stations,	remote	sensing, and	unmanned	vehicles	such	as gliders and	drones,	depending	in	

part	on	the	scale	of	coverage	one	seeks	to	achieve.