2. 2009 Norfolk Island Whale Survey Oosterman, Whicker & Garbett 2010
Introduction
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The seventh (7 ) consecutive Norfolk Island Whale Survey (NIWS) was conducted from Monday 12
October 2009 to Thursday 5 November 2009 under the authority of permit no. 2007-0004 as issued under
the Environment Protection and Biodiversity Conservation Act 1999 by the Commonwealth of Australia.
As was the case in previous such studies, all species of cetacean fauna were documented. Nevertheless,
the project continues to focus on the southward migration of humpback whales (Megaptera novaeangliae)
past Norfolk Island (29°02’S 167° 57’E). This report is the result of preliminary analyses of the raw data
obtained during the field component of the 2009 study. The intention is that this summary will be presented
at the April 2010 meeting in Auckland of the South Pacific Whale Research Consortium (SPWRC).
Summary
Since determining an apparent ‘peak’ in numbers from early October 2008 to early November of that year
(Oosterman, 2009) it was considered prudent to carry out the 2009 project within this window. Typically, the
duration of the annual Norfolk Island Whale Surveys has been approximately twenty-eight (28) days and
the 2009 project encompassed twenty-five (25) days (Table 1).
A significant portion of the on-effort hours of 2008 were not able to be replicated in 2009 due to inclement
weather. Norfolk Island, being an oceanic island, is susceptible to weather conditions that can be quite
variable. Unfortunately, during the field work component of the 2009 NIWS, less than ideal conditions
existed for much of the time. Indeed, on six (6) days out of 25 (24% of days) winds reached or exceeded
20knots and/or the Beaufort scale recorded was 4 or higher. In addition, mist over water or precipitation
limited visibility on some other days.
Typically, the NIWS team employs a number of strategic locations for its land-based observations. The key
site utilized during the 2008 survey was unable to be used per se in 2009 due to the proximity of nesting
Tasman boobies (Sula dactylatra tasmani). Instead, an adjacent tract of land situated approximately one
hundred metres (100m) to the west yielded a suitable alternative location (Table 2).
During the 2009 NIWS, 159hrs 35mns were expended on-effort. For the same period during the extended
2008 survey the team spent 215hrs 05mns on-effort. Therefore, on-effort survey time in 2009 amounted to
73.95% of the on-effort hours in the corresponding period during 2008. Complementing the land-based
study were vessel-based observations which were limited to a total of 16hrs 20mns spread over four (4)
separate days.
In the same vein, 84 humpback whales were observed migrating southward past Norfolk Island during this
same period in 2008, whilst 20 of their conspecifics were documented in 2009 (Table 3). Hence, 23.8% of
the number of humpbacks observed in 2008 were recorded for 2009. The 2009 study was able to
determine that per on-effort hour, 0.150 whales were observed (cf. 0.455 during a similar corresponding
period in 2008) and 0.125 humpback whales (Table 1) were observed (cf. 0.390 during a similar
corresponding period in 2008). Furthermore, 83.35% of whales observed were identified as humpbacks (cf.
85.7% during a similar corresponding period in 2008) and 35.0% of humpbacks observed were calves (cf.
31% during a similar corresponding period in 2008).
Humpback whales have always been the key focus of the NIWS and remain so. However, all cetaceans
encountered during the study have been documented. With the exception of humpback whales and
bottlenose dolphins (Tursiops truncatus), the most frequently recorded cetacean taxa are minke whales
(Balaenoptera spp.). Since 2004 minkes have been observed by NIWS personnel, often in conjunction with
’bait’ (Clupeiformes) fish schools on which minkes and sea birds, e.g., wedgetail shearwaters (Puffinus
pacificus) feed. No minke whales were observed by the team during the survey of 2009 (Table 3) yet during
the corresponding period of 2008, three (3) minkes were noted. Significantly, ‘bait’ fish were less abundant
and smaller in school size in 2009 than for 2008.
The current study yielded little in terms of cetacean biodiversity. Whilst four (4) large cetaceans were
unidentified to species (Table 3), taxa positively identified and photographed were offshore bottlenose
dolphins (Tursiops truncatus), humpback (Megaptera novaeangliae) and sperm whales (Physeter
macrocephalus). An anecdotal report (dated 03 April 2003) from the late Ian Kenny exists of the latter
species in the vicinity of Norfolk Island but the photographic evidence obtained (Figure 4) of five (5)
individuals - a pod of two (2) and a pod of three (3) in close proximity to each other - on 25 October within
sight of the island confirms the species for the region. Sloughed skin (#Mn09NI002, #Mn09NI003,
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3. 2009 Norfolk Island Whale Survey Oosterman, Whicker & Garbett 2010
#Mn09NI004) collected from one (1) of the sperm whales has been delivered to Dr Luciana Möller of
Macquarie University for genetic analysis.
Materials & Observer Effort
The 2009 survey team essentially consisted of Adrian Oosterman, Merv Whicker, Sue Goodfellow and
Borry Evans. For the corresponding period during the 2008 study these personnel were complemented by
four interns working on a roster basis.
Some of the key equipment used to facilitate the process of observing, photographing and recording whales
during the 2009 NIWS included Gerber 7 x 50 7.1 field binoculars, Fujinon 7 x 50 7.0 field compass
binoculars set for Southern Hemisphere specifications, Nikon 12 x 50 5.5 field binoculars, a Pentax 35mm
SLR digital *ist DL camera, a Garmin GPS 72 Personal Navigator, a Sony MZ-B100 Mini Disc recorder and
a High Tech 96-MI model hydrophone.
Acknowledgements
The 2009 NIWS was carried out with the considerable support of a number of individuals and organizations.
Sincere thanks are extended to Darren Bates, David Bigg for providing sperm whale photographs, Gaelene
Christian (Norfolk Window), Howard Christian for providing his vessel free of charge, Ken and Margaret
Christian, Borry Evans for accommodation as well as supply of vessel and his dedication, Claire Garrigue,
Sue Goodfellow, Chris Kenny, the late Ian Kenny (to whom this work is dedicated), Joan Kenny, Luciana
Möller, Ken Nobbs (Cameralines), Southern Cross University Whale Research Centre, The Norfolk Islander
(Jonathon Snell) and any others I may have been remiss in mentioning. Thanks is extended to all those
who recommended that the Norfolk Island Whale Survey continue. A special mention of gratitude is
expressed to Merv Whicker, whose assistance and perseverance with this survey, has greatly contributed
to its success.
The Australian Whale Conservation Society (AWCS) generously provided a grant that significantly defrayed
the financial burden of travel to Norfolk Island for the field component of the study and to New Zealand for
the 2010 SPWRC meeting where this report was delivered.
References
Garbett, P. (2009) Norfolk Island Whale Survey: humpback whale fluke photo-ID catalogue. 9pp. NIWS { Available from
cetalfauna@hotmail.com }
Oosterman, A. (2009) A review of the 2008 Norfolk Island Whale Survey. 7pp. NIWS { Available from
adrianoosterman@hotmail.com }
Oosterman, A. and Whicker, M. (2008). Norfolk Island Whale Surveys: reviewing the observations of 2003-2007.
(unpublished) 9 pp. NIWS { Available from adrianoosterman@hotmail.com }
Shirihai, H. (2006). Whales, dolphins and seals: a field guide to the marine mammals of the world. A & G Black
Publishers, London. 384 pp.
Correspondence
Adrian Oosterman, Norfolk Island Whale Survey, PO Box 143 Scarborough, Qld 4020, Australia
adrianoosterman@hotmail.com
61 7 3038 8131
61 418 984 324
This document may be cited as:
Oosterman, A., Whicker, M. and Garbett, P. (2010) A review of the 2009 Norfolk Island Whale Survey. 6 pp. Norfolk
Island Whale Survey.
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