2009 niws report

A Review of the 2009

Norfolk Island Whale Survey

Dedicated to THE LATE IAN KENNY

A preliminary report for submission to the April 2010 meeting of the South Pacific Whale Research Consortium

________________________________________________________________________

© 2010 Norfolk Island Whale Survey

2009 Norfolk Island Whale Survey Oosterman, Whicker & Garbett 2010

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Introduction

The seventh (7th) 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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#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 [email protected] }

Oosterman, A. (2009) A review of the 2008 Norfolk Island Whale Survey. 7pp. NIWS { Available from [email protected] }

Oosterman, A. and Whicker, M. (2008). Norfolk Island Whale Surveys: reviewing the observations of 2003-2007. (unpublished) 9 pp. NIWS { Available from [email protected] }

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 [email protected] 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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Table 1. Schedule of dates for cetacean research at Norfolk Island 2003 – 2009 showing number of humpbacks

observed per on-effort hour during each annual survey.

Year Survey Start Survey Finish Duration Humpbacks per on-effort Hour

2003 12.07.2003 19.07.2003 8 days 0.095

2004 27.08.2004 19.09.2004 24 days 0.017

2005 15.09.2005 12.10.2005 28 days 0.069

2006 17.09.2006 14.10.2006 28 days 0.068

2007 01.07.2007 28.07.2007 28 days 0.042

2008 23.08.2008 13.11.2008 83 days 0.232

2009 12.10.2009 05.11.2009 25 days 0.125

Table 2. Norfolk Island land-based survey locations 2009.

Observation

Platform

Elevation Latitude/

Longitude

Anson Point 50m 29 00.482S 167 55.342E

Captain Cook Lookout

85m 29 00.157S 167 56.615E

Cascade Lookout

77m 29 01.402S 167 58.391E

Crystal Pool 52m 29 03.644S 167 56.190E

Point Howe 94m 28 59.782S 167 55.466E

Puppy’s Point

85m 29 01.345S 167 55.297E

Queen Elizabeth II Lookout

92m 29 03.227S 167 57.839E

Steeles Point 85m 29 01.738S 167 59.683E

Table 3. Numbers of large cetacean species observed in Norfolk Island vicinity 2003 – 2009. Note the duration of

each survey is shown in Table 1.

Table 3: Number of large cetacean

species observed per year

0000

20202020

40404040

60606060

80808080

100100100100

120120120120

2003200320032003 2004200420042004 2005200520052005 2006200620062006 2007200720072007 2008200820082008 2009200920092009

humpbackhumpbackhumpbackhumpback

minkeminkeminkeminkeunidentifiedunidentifiedunidentifiedunidentified

spermspermspermsperm

© A.Oosterman / Norfolk Island Whale Survey


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Figure 1. Cascade observation location situated immediately to right of residence in centre of photo.

Photograph © Adrian Oosterman.

Figure 2. Virtually no photo-id opportunities existed during the 2009 NIWS. This animal was less than cooperative.


Figure 3. Humpback whale (Megaptera novaeangliae) encountered on 26 October 2009.



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Figure 4. Sperm whales (Physeter macrocephalus) to the north of Norfolk Island on 25 October 2009.

Photograph © David Bigg.

VALE . . . IAN KENNY

2009 niws report

Technology