Mark Deakos

Mark H. Deakos, Ph.D.

President, Founder, Chief Scientist

Dr. Deakos was fortunate to experience living in various countries around the globe during his early years. A common thread in his life has always been water. At one time a competitive swimmer and water polo player, Dr. Deakos now spends much of his time in saltwater as an avid scuba diver, free diver, kayaker, and mariner. His chosen career working in wildlife biology and marine research is an extension of his passion for the natural world and his marvel of the ocean environment. Dr. Deakos obtained his biology degree from the University of Waterloo in Canada where he began pursuing his interest in wildlife biology.

Dr. Mark H. Deakos. PhD

After working with several avian and reptile species, his interests rapidly returned to the ocean and towards marine mammals, which eventually led him to Hawaii in 1996. At the University of Hawaii, he completedhis master’s degree studying humpback whale behavior and continued his graduate work by completing his doctoral degree with a focus on manta ray ecology. Over the past decade in Hawaii, Dr. Deakos has worked alongside top researchers in the world gaining familiarity with over 20 species of marine mammals ranging from elusive beaked whales to fearless false killer whales.

As a result of his participation in these various projects, Dr. Deakos has developed invaluable research skills. Some of these include: satellite and suction cup tag deployment, aerial surveying, photo-identification, biopsy collection, acoustic monitoring, theodolite tracking, underwater photogrammetry, and behavioral data collection. Dr. Deakos was the project field coordinator for the University of Hawaii’s Humpback Whale Research Program for seven consecutive years. His experiences have taught him the necessity of understanding our environment in efforts to better protect it from ecological or man-made threats.


Publications

McCauley, D. J., DeSalles, P. A., Young, H. S., Papastamatiou, Y. P., Caselle, J. E., Deakos, M. H., … & Micheli, F. (2014). Reliance of mobile species on sensitive habitats: a case study of manta rays (Manta alfredi) and lagoons. Marine Biology, 161(9), 1987-1998.
Abstract or Full PDF (279 kb)

Deakos M.H. (2012) The reproductive ecology of resident manta rays (Manta alfredi) off Maui, Hawaii, with an emphasis on body size. Environmental Biology of Fishes, 94(2):443-456
Abstract or Full PDF (279 kb)

Thorne, L. H., Johnston, D. W., Urban, D. L., Tyne, J., Bejder, L., Baird, R. W., Yin, S., Rickards S. H., Deakos, M. H., Mobley, J. R., Pack A. A., Hill, M. C. (2012). Predictive modeling of spinner dolphin (Stenella longirostris) resting habitat in the main Hawaiian Islands. PloS one, 7(8), e43167.
Abstract or Full PDF (1.9 mb)

Deakos M.H., Baker, J.D., Bejder, L. (2011) Characteristics of a manta ray Manta alfredi population off Maui, Hawaii, and implications for management. Marine Ecology Progress Series, 429:245-260
Abstract or Full PDF (340 kb)

Deakos M. (2010) The ecology and social behavior of a resident manta ray (M. alfredi) population off Maui, Hawaii. Doctoral Thesis, University of Hawaii, Manoa.
Abstract or Full PDF (1.8 mb)

Deakos M. (2010) Paired-laser photogrammetry as a simple and accurate system for measuring the body size of free-ranging manta rays Manta alfredi. Aquatic Biology 10:1-10
Abstract or Full PDF (492 kb)

Deakos M.H., Branstetter, B.K., Mazzuca, L., Fertl, D., Mobley J.R.Jr. (2010) Two unusual interactions between a bottlenose dolphin (Tursiops truncatus) and humpback whale (Megaptera novaeangliae) in Hawaiian waters. Aquatic Mammal,s 36(2):121-128
Abstract or Full PDF (836 kb)

Pack, A., Herman L., Spitz S., Hakala S., Deakos M., Herman E. (2009) Male humpback whales in the Hawaiian breeding grounds preferentially associate with larger females. Animal Behavaviour, 77(2):653-662
Abstract or Full PDF (385 kb)

Baird, R.W., A.M. Gorgone, D.J. McSweeney, A.D. Ligon, M.H. Deakos, D.L. Webster, G.S. Schorr, K.K. Martien, D.R. Salden, S.D. Mahaffy. (2008). Population structure of island-associated dolphins: evidence from photo-identification of common bottlenose dolphins (Tursiops truncatus) in the main Hawaiian Islands. Marine Mammal Science, 23(2): 251-274
Abstract or Full PDF (500 kb)

Baird, R.W., A.M. Gorgone, D.J. McSweeney, D.L. Webster, D.R. Salden, M.H. Deakos, A.D. Ligon, G.S. Schorr, J. Barlow and S.D. Mahaffy. (2008). False killer whales (Pseudorca crassidens) around the main Hawaiian Islands: long-term site fidelity, inter-island movements, and association patterns. Marine Mammal Science, 24(3): 591-612
Abstract or Full PDF (336 kb)

Au, W. W. L., Pack, A. A., Lammers, M. O., Herman, L. M., Deakos, M. H., Andrews, K. (2006). Acoustic properties of humpback whale songs. The Journal of the Acoustical Society of America, 120(2), 1103-1110
Full PDF (618 kb)

Au, W. W. L., Pack, A. A., Lammers, M. O., Herman, L. M., Andrews, K., & Deakos, M. H. (2003). The acoustic field of singing humpback whales in the vertical plane. The Journal of the Acoustical Society of America, 113(4): 2277-2277
Abstract

Deakos, M. H. (2002). Humpback whale (Megaptera novaeangliae) communication: The context and potential functions of pec-slapping behavior on the Hawai’ian wintering grounds. Masters Thesis, University of Hawaii, Manoa.
Abstract or Full PDF (860 kb)

Spitz, S. S., Herman, L. M., Pack, A. A., & Deakos, M. H. (2002). The relation of body size of male humpback whales to their social roles in the Hawaiian winter grounds. Canadian Journal of Zoology, 80(11): 1938-1947
Abstract or Full PDF (216 kb)

Pack, A. A., Herman, L. M., Craig, A. S., Spitz, S. S., & Deakos, M. H. (2002). Penis extrusion by Megaptera novaeanglieae). Aquatic Mammals, 28(2): 131-146
Abstract or Full PDF (1991 kb)

Reports

Hill, M. C., Ligon, A. D., Deakos, M. H., Ü5, A. C., Milette-Winfree, A., Bendlin, A. R., & Oleson, E. M. (2014). Cetacean Surveys in the Waters of the Southern Mariana Archipelago (February 2010-April 2014). PIFSC Data Report DR-14-013, Issued 2 September 2014
Abstract or Full PDF (2.6 mb)

Baird, R.W., A.M. Gorgone, D. L. Webster, D.J. McSweeney, J.W. Durban, A.D. Ligon, D.R. Salden, and M.H. Deakos. 2004. False killer whales around the main Hawaiian islands: an assessment of inter-island movements and population size using individual photo-identification. Report prepared under Order No. JJ133F04SE0120 from the Pacific Islands Fisheries Science Center, National Marine Fisheries Service, 2570 Dole Street, Honolulu, HI 96822
Abstract or Full PDF (886 kb)

Conference Proceedings

Deakos, Mark, Jason Baker, Allan Ligon, Jonathan Whitney, Tim Clark (2008). Demographics of an Island-Associated Manta Ray (Manta birostris) Population in Maui, Hawaii, and Implications for Management. Abstract, 88th annual meeting of the American Society of Ichthyologists and Herpetologists, Montreal, Canada
Abstract

Deakos, Mark (2008). Using Paired-Laser Photogrammetry for Measuring Manta Ray (Manta birostris) Sizes. Are Maui’s Mantas Horizontally Challenged? Abstract, 88th annual meeting of the American Society of Ichthyologists and Herpetologists, Montreal, Canada
Abstract

Pack, A. A., Herman, L. M., Deakos, M. H., Hakala, S., Craig, A. S., Olson, J.R., Spitz, S. S., Herman, E., Goetschius, K., & Lammers, M. O. (2005). First report of sounds recorded from individual humpback whale calves on the Hawaiian wintering grounds. Abstract, 16th Biennial conference on the biology of marine mammals, San Diego, CA.
Abstract

Adam A. Pack, John R. Potter, Louis M. Herman, Mark H. Deakos, Matthias Hoffmann-Kuhnt (2003) Determining source levels and sound fields for singing humpback whales (Megaptera novaeangliae) on the Hawai’ian wintering grounds. Talk presented at the Environmental Consequences of Underwater Sound (ECOUS) Symposium
Abstract

Pack, A. A., Au, W.W.L., Lammers, M. O., Herman, L., & Deakos, M. (2003). Determining the acoustic field and transmission characteristics for singing humpback whales on the Hawaiian winter grounds. Abstract, 15th Biennial conference on the biology of marine mammals, Greensboro, NC
Abstract

Deakos, M. H., Pack, A. A., Herman, L. M., Spitz, S. S. (2001). Why do humpback whales slap their pectoral fins in competitive groups? Abstract, 14th Biennial conference on the biology of marine mammals
Abstract

Deakos, M. H., Pack, A. A., Herman, L M., Spitz, S. S., Craig, A. S. (1999). Survival and recovery of a humpback whale calf with a grievous propeller wound. Abstract, 13th Biennial conference on the biology of marine mammals, Maui, HI
Abstract

Talks and Lectures

Manta Photogrammetry Presentation & Research (2016), in conjunction with Manta Trust, Six Senses Resorts, Laamu Atoll, Maldives

Ecology and Social Behavior of a Manta Ray (Manta alfredi) Population of Maui, Hawaii (2010), University of Hawaii, Honolulu, Hawaii

Maui’s Majestic Mantas (2009), Maalaea Village, Maalaea, Hawaii

The Open Ocean, The Source of All Life (2008), Lahaina Civic Center, Lahaina, Hawaii

Humpback Whales and the State of our Planet (2007), Kamehameha Elementary School, Lahaina, Hawaii

Humpback Whales: Their Past, Present, and Future (2006), Sea Grant & Malama Kai Foundation, Kailua-Kona, Hawaii

Humpback Whales: Their Past, Present, and Future (2006), Hawaiian Islands Humpback Whale National Marine Sanctuary, Kihei, Maui

Humpback Whales: Their Past, Present, and Future (2006), Hawaiian Islands Humpback Whale National Marine Sanctuary, Lihue, Kauai

Humpback Whales: Their Past, Present, and Future (2004), Hawaiian Islands Humpback Whale National Marine Sanctuary, Lihue, Kauai

Hawaii’s Marine Mammals – Do you know what you are watching? (2004), Training lecture, Radisson Beach Resort, Lihue, Kauai

Humpback Whales: Their Past, Present, and Future (2004), Hanauma Bay Education Program, Hanauma Bay, Oahu

Hawaii’s Marine Mammals – Do you know what you are watching? (2004), Training lecture, Hawaiian Islands Humpback Whale National Marine Sanctuary Office, Hawaii Kai, Oahu

Humpback Whales: Their Past, Present, and Future (2004), Outrigger Keauhou Beach Resort, Kailua-Kona, Hawaii

Hawaii’s Marine Mammals – Do you know what you are watching? (2004), Training lecture, Outrigger Keauhou Beach Resort, Kailua-Kona, Hawaii

Humpback Whales: Their Past, Present, and Future (2004), Hawaiian Islands Humpback Whale National Marine Sanctuary Office, Kihei, Maui

Hawaii’s Marine Mammals – Do you know what you are watching? (2004), Training lecture, Hawaiian Islands Humpback Whale National Marine Sanctuary Office, Kihei, Maui

Hawaii’s Humpback Whales (2003), Hanauma Bay Education Program, Hanauma Bay, Oahu

Humpback Whale Behavior and Biology (2003) High-School Teacher Continuing Education Credit, Kihei, Maui

Humpback Whales: Current Research Findings (2002), Ocean Arts Festival, Lahaina, Maui

Studying Humpback Whales (2000), Island Marine Institute Internship program, Lahaina, Maui

ABSTRACTS

False killer whales around the main Hawaiian islands: an assessment of inter-island movements and population size using individual photo-identification
Baird, R.W., A.M. Gorgone, D. L. Webster, D.J. McSweeney, J.W. Durban, A.D. Ligon, D.R. Salden, and M.H. Deakos.
Report prepared under Order No. JJ133F04SE0120 from the Pacific Islands Fisheries Science Center, National Marine Fisheries Service, 2570 Dole Street, Honolulu, HI 96822, April 5, 2005

Abstract

The current best estimate of population size for false killer whales within Hawaiian waters is only 268 individuals (Barlow 2003), though the estimate is not very precise (CV = 1.08). False killer whales are considered a “strategic” stock by the National Marine Fisheries Service, as “takes” in the Hawai‘i-based swordfish and tuna long-line fishery exceed the “Potential Biological Removal” (PBR) level. We studied false killer whales as part of small-boat based surveys for odontocetes around the main Hawaiian islands from 2000 through 2004, and in this report we assess inter-island movements, examine “mark” change over time on individual animals, estimate the proportion of marked individuals within the population, and provide a mark-recapture population estimate. Dedicated surveys for odontocetes were undertaken around all the main Hawaiian islands, and all groups of false killer whales encountered were approached and attempts made to photographically identify all individuals present. False killer whales were encountered on 14 occasions in directed surveys (2.9% of all odontocete sightings), in eight of the 10 months of the year surveyed, and in three of the four island-areas surveyed. Encounters were in a wide range of water depths (37 to 3,950 m). Photographs from seven opportunistic encounters were also available. Seventy-seven percent of individuals photographed were considered to have markings that could be recognized in the long-term (between-years). Seventy-six individuals with such long-term markings were documented, 47 of which were seen on two or more occasions. Ten individuals were documented with mark changes, though the rate of mark change was low (approximately one change every six years). Re-sighting analysis suggest that there are considerable inter-island movements of individuals (for example, 19 of 21 individuals identified off O‘ahu have been recorded off the island of Hawai‘i or around the “4-islands”). A multi-site mark-recapture analysis, taking into the proportion of marked individuals in the population, resulted in an estimate of 123 individuals in the population (CV = 0.72). This estimate applies to a population of false killer whales that used the study area; however the geographic range of that population is not known. Also, we assumed population closure and homogenous capture probabilities among individuals. The degree to which these assumptions may have been violated and the resulting estimate biased remain unclear.


The acoustic field of singing humpback whales in the vertical plane
Au, W. W. L., Pack, A. A., Lammers, M. O., Herman, L. M., Andrews, K., & M. H. Deakos
The Journal of the Acoustical Society of America, April 2003, Volume 113, Issue 4, p. 2277

Abstract

A vertical array of five hydrophones was used to measure the acoustic field of singing humpback whales. Once a singer was located, two swimmers with snorkel gear were deployed to determine the orientation of the whale and to position the boat so that the array could be deployed in front of the whale at a minimum standoff distance of 10 m. The spacing of the hydrophones was 7 m with the deepest hydrophone deployed at depth of 35 m. An 8-channel TASCAM recorder having a bandwidth of 24 kHz was used to record the hydrophone signals. The location of the singer was determined by computing the time of arrival differences between the hydrophone signals. The maximum source level varied between individual units in a song, with values between 180 and 190 dB. The acoustic field determined by considering the relative intensity of higher frequency harmonics in the signals indicate that the sounds are projected in the horizontal direction with the singer’s head canted downward 45 to 60°. High-frequency harmonics extended beyond 24 kHz, suggesting that humpback whales may have an upper frequency limit of hearing as high as 24 kHz.


Determining source levels and sound fields for singing humpback whales (Megaptera novaeangliae) on the Hawai’ian wintering grounds
Adam A. Pack, John R. Potter, Louis M. Herman, Mark H. Deakos, Matthias Hoffmann-Kuhnt
ECOUS Symposium, 12-16 May 2003, San Antonio, Texas

Abstract

Male humpback whales (Megaptera novaeangliae) on their wintering grounds produce complex vocalizations termed “song.” The stereotypical stationary posture adopted by singers suggests they are attempting to optimize transmission range. In March 2002, we measured the sound fields of singers using divers equipped with rebreather scuba. A customdesigned ‘Aquahead’ system reliably located ECOUS Symposium 12-16 May 2003 San Antonio, TX 10 singers to within 30 m. Fourteen singers were located from as far away as 8.2 km and in times of 11-48 min. The rebreathers enabled divers to descend to the singer with minimal expulsion of bubbles and noise. Divers moved in arcs around the singer to sample song at various orientations using digital video cameras while simultaneously measuring depth and range to the singer’s head using handheld ultrasonic range meters. At the end of a song a snorkeler used our videogrammetric technique to measure singer body length. Initial signal processing of five singers indicates source powers of up to 190 dB re 1 microPa @ 1 m with a directionality oriented in front of the singer’s head, lateral power levels being up to 18 dB below those in front at some frequencies. Higher frequencies were observed to have a higher directionality than lower frequencies.


The relation of body size of male humpback whales to their social roles on the Hawaiian winter grounds
Scott S. Spitz, Louis M. Herman, Adam A. Pack, and Mark H. Deakos
Canadian Journal of Zoology, 2002. Volume 80, Issue 11, pp. 1938-1947

Abstract

We examined the relation of body length of male humpback whales (Megaptera novaeangliae) to the social roles they adopted on the Hawaiian winter grounds: principal escort in a competitive group, secondary escort, lone escort to a mother–calf pair, male partner in a dyad, and singer. Using underwater videogrammetry, we measured body lengths of 17 principal escorts, 68 secondary escorts, 40 single escorts, 17 male partners, and 8 singers. Results revealed that (i) principal escorts were, on average, significantly larger than males in each of the remaining social roles except singer, (ii) singers were significantly larger than male partners, (iii) there were no significant size differences among secondary escorts, single escorts, or male partners. Further, principal escorts tended to be the largest or second-largest male within their individual competitive group. All principal escorts were of sizes that indicated a 0.81 probability or better of sexual maturity, based on whaling data. In comparison, more than half of the male partners, almost one-third of the secondary escorts, and one-fifth of the single escorts were of sizes that indicated a 0.5 probability or less of sexual maturity. Seven of the eight singers had a 0.9 probability or better of sexual maturity and the eighth singer a 0.5 probability. However, the data for singers are too few to allow firm conclusions to be reached about the relation of body size to singing. Overall, our findings suggest that body size confers an advantage in physical competition between male humpback whales, and that a large proportion of males adopting the role of secondary escort, single escort, and partner are likely to be sexually immature. Additionally, the competitive group appears to be a major reproductive unit in terms of bringing together a receptive female and potential mates.


Humpback whale (Megaptera novaeangliae) communication: The context and potential functions of pec-slapping behavior on the Hawai’ian wintering grounds
Deakos, M. H.
Unpublished Masters Thesis, University of Hawaii, Manoa, 2002

Abstract

Humpback whales display a variety of percussive behaviors that may function as communication between conspecifics. Pectoral-fin slapping behavior is commonly observed in a variety of marine mammals including seals, dolphins, and humpback whales. Data from 5-years of behavioral observations of humpback whales on the Hawaiian wintering grounds were compiled and analyzed. Overall findings suggest pecslapping behavior is dependent on the performer’s age class, sex, and social role. Adult females appear to pec-slap in competition groups in efforts to encourage competition from surrounding males, indicating her readiness to mate. Adult males pec-slap while disaffiliating from other males, possibly in attempts to maintain a non-agonistic male association. Subadult pec slapping is likely a form of “play”, an important characteristic in the development, coordination, and learning in young mammals. These discoveries can serve as tools to enhance the interpretation of humpback whale social behavior, and provide a model for understanding other percussive behaviors.


Penis extrusions by humpback whales (Megaptera novaeangliae)
Pack, A. A., L. M. Herman, A. S. Craig, S. S. Spitz and M. H. Deakos
Aquatic Mammals, 2002, Volume 28, Issue 2, pp. 131-146

Abstract

The annual winter assembly of humpback whales (Megaptera novaeangliae) in tropical waters has been linked to reproductive activities, including birthing, calf-rearing, and mating. However, the sexual behaviour of this species remains largely undescribed and mating has never been witnessed. We examined 121 h of underwater videotaped footage of humpback whales obtained over five winter seasons in Hawaiian waters for evidence of penis extrusions by whales engaged in various activities in a range of social groups. In 630 different pods containing videotaped males, we noted 13 penis extrusion incidents. Penis extrusions were performed by lone singers (2 incidents), by the single escort to a mother/calf pair (6 incidents), and by principal and secondary escorts in competitive pods containing a female either with a calf (2 incidents) or without (3 incidents). All penis extrusions were brief (mean=44.0) s). Body length measurements (mean=11.53 m, SD=0.46 m, range=10.64 m to 12.05 m) were obtained using underwater videogrammetry on seven penis extruders, and suggested that the majority were sexually mature. Each penis extrusion in a competitive pod coincided with the penis extruder chasing another whale, and in four of five cases appeared to be directed toward another male. In the remaining case, the extruder appeared to attempt mating with a mother. Our findings suggest that penis extrusions in humpback whale competitive pods are often a concomitant of dominance contests between males.


Why do humpback whales slap their pectoral fins in competitive groups?
Deakos, M. H., Pack, A. A., Herman, L. M., and Spitz, S. S.
Poster presented at the 14th Biennial conference on the biology of marine mammals, Vancouver, Canada, November 28 – December 5, 2001

Abstract

Humpback whales on their wintering grounds are often observed in “competitive groups” composed of multiple males competing physically for proximity (principal escort position, PE) to a lone female (nuclear animal, NA) or to one accompanied by her calf (mother). Although several behaviors in competitive groups are clearly related to male-male aggression, others are less well understood. Slapping a pectoral fin against the water surface (pec slap) is sometimes observed in competitive as well as non-competitive groups. We investigated the social roles and contexts of pec slapping in competitive groups over 5 winter seasons (1997 – 2001) in Hawaiian waters. Overall, pec slapping was recorded in 256 (31%) of 831 competitive groups (the mature female (either NA or mother) pec slapped in 42% of the 256 groups, the PE in 5%, and secondary escorts in 17%). Of 636 NA competitive groups, the NA pec slapped in 94 (15%), compared with only 14 (7%) mothers pec slapping in 196 competitive groups (x2 = 7.1, p < .01). PEs pec slapped in only 3 (0.5%) of NA competitive groups compared with 9 (5%) in mother/calf competitive groups (x2 = 21.3, p < .001). Because mature female humpbacks without calf are more likely to conceive, NAs should theoretically have a higher reproductive potential than mothers (Craig, 2001). Males might therefore be expected to compete more vigorously in competitive groups without calf. The lower percentage of pec slapping by PEs in groups without calf suggests that pec slapping is not a principal competitive behavior employed by males. If pec slapping by females in competitive groups were related to female receptivity, it should be greatest in pods without calf. If it were related to deterring males, it should be greatest in competitive pods in which females are less receptive. Our findings are consistent with the first hypothesis.


Survival and recovery of a humpback whale calf with a grievous propeller wound
Deakos, M. H., Pack, A. A., Herman, L M., Spitz, S. S., and Craig, A. S.
Poster presented at the 13th Biennial conference on the biology of marine mammals, Wailea, Maui, USA, November 28 – December 3, 1999

Abstract

Recovery from serious injury has been well documented for dolphins. However, little data exist on the recuperative capabilities of baleen whales. Calves, because of their relatively small size, may be particularly vulnerable. In 1999, a humpback whale calf (C) with a deep gash in its back was observed on four occasions over 38 days in waters off Maui. The wound extended rostrally from the dorsal fin 31-cm, was 17-cm deep, penetrating through blubber, and stretched 56-cm down the left side. No bleeding was observed, and the presence of granulated tissue suggested that healing had begun. Three vertical lacerations indicated injury from a boat propeller. Changes in C’s behavior and its mother’s (M) dive duration provided evidence of C’s recovery. Initially, M attended C closely, repeatedly supporting C after it surfaced and rolled onto its side. Dive times for both M and C were only 30 s. Twenty-three days later, C surfaced with no apparent difficulty. However, it was still joined by M at each surfacing. Mean dive times for M and C were 3.68 and 2.80 min, respectively. Three days later C appeared energetic and behaved like healthy humpback calves. C milled at the surface before diving to M and breached repeatedly within a 5-min period following affiliations by multiple escorts. It traveled within this competitive group 8.53 km in 2 hr 15 min with top speeds reaching 4.59 km/hr. Eleven days later, C was again observed breaching as it traveled. Mean dive times increased to 6.36 min for M but remained relatively unchanged for C, possibly indicating C’s decreasing requirement for support at the surface. Although boat strikes are an increasing problem for cetaceans, our findings suggest that like dolphins, humpback whale calves are able to recover from some major physical traumas.