The Status of the Recovering Stock of Humpback Whales Megaptera novaeangliae in East Australian Waters
Robert Paterson & Patricia Paterson
PO Box 397, Indooroopilly, Queensland 4068, Australia
(Received 14 April 1988; accepted 6 June 1988)
ABSTRACT
In 1987, after 25 years'protection from whal&g operations, the portion of the Area V (130 ° E-170 ° W) humpback whale Megaptera novaeangliae stock which migrates along the east Australian coast was estimated to number approximately 1100 compared with fewer than 500 estimated for the whole of Area V at the end of whaling. The best estimate of the annual rate of increase is 10% with a 95% confidence interval of between 6% and 13%. Those estimates were calculated from data obtained during observations from headlands at latitude 27 ° S between 1981 and 1987. Reports from other areas confirm that sheltered waters of the Great Barrier Reef in the vicinity of latitude 20°S are an important calving ground for this stock, although some humpback whales calve at higher latitudes in east Australian waters.
INTRODUCTION
On the basis of comparison with the data of Chittleborough (1965), Paterson & Paterson (1984) considered that by 1982 the east Australian humpback whale Megaptera novaeangliae stock had begun to recover from the low numbers noted in 1962, the last year of commercial whaling in the region.
Various aspects of the stock have been studied in recent years including distribution in Great Barrier Reef waters (Simmons & Marsh, 1986), photo- identification of individuals (Kaufman et al., 1987), population dynamics (Bryden, 1985) and song characteristics (Cato, 1984). The results of observations of humpback whale migrations in the Cape Moreton/Point Lookout region of southern Queensland between 1983 and 1987 are presented in this paper together with sightings reported from other locations on the east Australian coast.
CAPE MORETON/POINT LOOKOUT OBSERVATIONS
The observation methods were similar to those described by Paterson & Paterson (1984). Cape Moreton (27002 , S, 153 ° 28' E) and Point Lookout (27 ° 26' S, 153 ° 33' E) are prominent headlands and their proximity to the former whaling stations at Byron Bay and Tangalooma is shown in Fig. 1. During the annual humpback whale migration the majority of whales pass north through this region during the winter months (June-August) and pass south during spring and summer (September and October) (Figs 2 and 4). There are approximately 10.5 h of light each day during June/July at latitude 27 ° S and 12.5 during September/October. We kept watch during all daylight hours when we were at Cape Moreton or Point Lookout from early June to late October. The sighting data are contained in Table 1 and Fig. 2.
Unseasonal weather disrupted observation of the northern migrations in 1983 and 1985. In the former year cyclonic conditions occurred in late June and in the latter 213 mm of rain were recorded at Point Lookout during the first nine days of July. Chittleborough (1965) noted that whalers occasionally blamed unfavourable weather for poor catches but concluded that weather was not an important factor in catch variation. However, the lowest monthly catch of northbound humpback whales in the decade (1952-1962) of east Australian whaling occurred in July 1962 when the rainfall of 399 mm at Point Lookout was the highest recorded for the month of July in the entire whaling period (Durbidge & Covacevich, 1981). While the reduced catch was primarily due to depletion of the humpback whale stock (Chittleborough, 1965) it is possible that poor weather contributed to the lack of sightings.
Based on the time of day of first sighting of 187 humpback whale groups between 1978 and 1982, Paterson & Paterson (1984) considered that other groups may have passed undetected during the period of mid-morning glare. However, the time of first sighting of 936 groups between 1983 and 1987 (Fig. 3) demonstrates only a slight reduction during mid-morning compared with the following hours and the earlier opinion may have been based on
Humpback whales in Australian waters 35
27oS Cape Moreton
M o r e t o n I s l and
)Point Lookout
South Pac i f ic O c e a n
Nor th S t r a d b r o k e I s l and
Q L E E N S L A N D
28oS
NEV
i _ i
S O U T H W A L E S
GN jN , Scale i
O 10 20 km
153OE
Byron Bay
Fig. 1. Map of the Cape Moreton/Point Lookout region on the east Australian coast. The sites of the former whaling stations at Byron Bay and Tangalooma are shown.
insufficient data. Other features of the hourly sighting rates deserve comment. Owing to insufficient light no sightings were made before 0600 h or after 1700h during the northern migration. The high sighting rate between 0600 and 0800h can be explained by assuming that humpback whales, which might have been seen earlier if there had been sufficient light, were still within visible range. The period of early daylight is excellent for the detection of a whale blow and similar opinions were expressed by shore- based observers during whaling operations in the Azores (Clarke, 1954) and the Cook Strait of New Zealand (Grady, 1982). We consider that the period of mid-morning glare is difficult for whale sighting and the difficulty is
36 Robert Paterson, Patricia Paterson
TABLE 1 Humpback Whales Sighted from Cape More ton /Poin t Lookout between 1983 and 1987
Year Week ended Hours o f Whales sighted Whales sighted observation per 10 h
North South North South
1983 25 June 15"00 5 0 3'33 - - 1983 2 July 73'50 31 0 4"21 - - 1983 9 July 60.00 35 0 5"80 - - 1983 16 July 42.00 12 0 2-85 - - 1983 10 September 36"00 0 15 - - 4"16 1983 24 September 48"00 2 28 0"41 5"83 1983 1 October 78.00 0 21 - - 2.69 1983 15 October 27.00 0 23 - - 8-51 1984 23 June 55.00 24 0 4"36 - - 1984 30 June 73"25 32 0 4.36 - - 1984 7 July 54-00 46 0 8'51 - - 1984 14 July 34"50 25 0 7'24 - - 1984 22 September 88"50 12 47 1.35 5.34 1984 29 September 62"00 4 26 0-64 4' 19 1984 6 October 73"50 0 25 - - 3'40 1984 13 October 57-00 0 23 - - 4.03 1985 22 June 52.50 22 0 4-19 - - 1985 29 June 73'50 35 0 4-89 - - 1985 6 July 49.00 29 0 5"91 - - 1985 13 July 50.00 34 0 6'80 - - 1985 20 July 51.00 31 0 6"08 - - 1985 14 September 55'25 0 48 - - 8"67 1985 21 September 57-25 3 2 0-52 0-34 1985 28 September 79"50 1 35 0.12 4-40 1985 5 October 79'50 4 44 0"53 5"90 1986 21 June 63"00 32 0 5"07 - - 1986 28 June 73-00 80 0 10'95 - - 1986 5 July 51"50 28 0 5'54 - - 1986 12 July 53"00 56 0 10.56 - - 1986 19 July 45.50 27 1 5-93 0"21 1986 26 July 45.50 23 0 5"05 - - 1986 30 August 58'75 10 20 1-70 3-40 1986 6 September 57.25 9 30 1.57 5.24 1986 27 September 83-50 9 84 1'07 10"06 1986 4 October 63.00 5 25 0"79 3-96 1987 6 June 39"50 4 0 1-01 - - 1987 13 June 41.00 16 0 3'90 - - 1987 20 June 38-50 19 0 4.96 - - 1987 27 June 36.00 35 0 9.72 - - 1987 4 July 49.00 35 0 7.14 - - 1987 11 July 54-00 50 0 9.25 - -
Humpback whales in Australian waters
T A B L E l--contd.
37
Year Week ended Hours o f Whales sighted Whales sighted observation per 10 h
North South North South
1987 18 July 47"50 38 0 8.00 - - 1987 25 July 41"00 22 0 5-36 - - 1987 1 August 35-50 18 0 5'07 - - 1987 8 August 38-25 5 0 1-30 - - 1987 15 August 29"00 3 0 1"03 - - 1987 22 August 29'25 1 5 0"34 1"63 1987 29 August 54"50 14 24 2"56 4"40 1987 5 September 49-50 7 23 1.41 4"65 1987 12 September 41"75 4 31 0-95 7-42 1987 19 September 44.00 2 43 0.45 9-77 1987 26 September 49.00 I 32 0-20 6"53 1987 3 October 65"00 2 43 0.30 6"61 1987 10 October 54.00 5 20 0-92 3-70 1987 17 October 43'50 7 41 1.60 9'42 1987 24 October 41.00 0 17 - - 4.14 t987 31 October 47-50 2 22 0.42 4"63
Fig. 2. Number of humpback whales seen from Cape Moreton/Point Lookout per 10 h of observation during 1987.
38 Robert Paterson, Patricia Paterson
D 1 2 0 uJ I - ~ 1 1 0
1 0 0
~ 9 0 0
I,~ 8 O
< 7 0 Z
~ 6O
0 < 5 0 m L IE 4 0
Z 3 0 IL
0 ~e 2 0 ul m Z 10
Z
T I M E 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 ~- ~ ~.- ~- v- ~- ~- ~- ~.
Fig. 3. T i m e o f first s i gh t ing o f 936 h u m p b a c k wha l e g r o u p s , 1983-1987.
compounded during the southern migration when haze associated with mainland fires and warm northerly winds reduces visibility.
Although the majority of northbound humpback whales have passed latitude 27°S by early August (Table 1 and Fig. 2), the numbers passing north between late August and the end of October are not insignificant. In 1987 'late' northbound humpback whales comprised 15-5% of the total observed (Table 1). It is possible that some of those were about to calve as analysis of the previous southern hemisphere catch data indicated that humpback whales in advanced pregnancy predominated in the terminal phase of the northern migration (Dawbin, 1966). Because some southbound humpback whales adopt an irregular course (Paterson, 1984a), strict criteria were used for the recording of northbound humpback whales during late August, September and October. They included small group size (singles or pairs), rapid speed and undeviating course. Observations of northbound humpback whales at times when the expected migratory direction was southwards were recorded by the Byron Bay and Tangalooma whalers and the data (from Chittleborough, 1965) are shown in Fig. 4. Observations of 'late-season' humpback whales have also been reported from Alaska in the North Pacific Ocean (Baker el a/., 1985). There is no evidence of an 'early' southern migratory phase in east Australian waters. Apart from a single animal seen on 19 July 1986, no southbound humpback whales were seen in
Humpback whales in Australian waters 39
the Cape Moreton/Point Lookout region during July between 1983 and 1987 (Table 1).
In 1987 we ceased observations at the end of October although substantial numbers of southbound humpback whales were still being seen (Fig. 2). The period of observation conformed with that in 1961 when whaling operations were conducted for the maximum permitted time in an attempt to fill the allotted quota (Chittleborough, 1965).
Week ending 2 9 16 23 30
Fig. 4.
15
o 14
a 13
~ 1 2 o
o n 1 0
• 9
"3 8
,a 5
E ~ 4 o 3
® .a 2
z 1
1777~ N o r t h ~ S o u t h I C o w s with ca lves
, v , • ~
JUNE
15 22 291 5 12 19 26
JULY AUGUST SEPTEMBER OCTOBER
Number of humpback whales seen in the vicinity of latitude 28°S on the east Australian coast per 10 h of hunting during 1961 (from Chittleborough, 1965).
Chittleborough (1965) documented, without comment, the lack of a distinct peak during the southern migration in 1961 in contrast to the sharp peak during the northern migration (Fig. 4). Paterson (1984a) demonstrated similar patterns in 1982 and 1983 and concluded that the phenomenon was a constant feature of humpback whale migration in east Australian waters and that the 1961 southern migration pattern did not result from a high mortal i ty of no r thbound humpback whales in that year. Fur ther observations in recent years (Table 1 and Fig. 2) confirm the patterns, although a bimodal peak with one week's separation was noted during the northern migration in 1986 and 1987.
40 Robert Paterson, Patricia Paterson
OBSERVATIONS FROM OTHER EAST COAST LOCATIONS
Between 1983 and 1986 an annual request for notification of humpback whale sightings was published in Australian Fisheries, a journal circulated inter alia to all holders of Australian commercial fishing licences. The resultant data are presented in Figs 5 and 6 in a manner similar to those obtained between 1979 and 1982 (Paterson & Paterson, 1984). Each marking refers to one or more humpback whale groups seen during a particular month in one or more of the survey years and the figures demonstrate the spatial and temporal distribution of humpback whales in east Australian waters. Concentration of humpback whales in the central section of the Great Barrier Reef between July and September is shown. Three eye-witness accounts of humpback whale calving were reported from that region (Table 2).
TABLE 2 Humpback Whale Calving Witnessed in Great Barrier Reef Waters
Date Location Reference
Mid-August 1982
9 August 1984
14 September 1985
Little Trunk Reef (18° 21'S, 146° 51'E)
Charity Reef (19° 23' S, 148° 21' E)
Little Broadhurst Reef (18° 58' S, 147°41' E)
Paterson (1984b)
Paterson (1987)
Paterson (1987)
Analysis of available log books from 19th century American whale-ships indicated that humpback whales calved in the vicinity of latitude 20 ° in their respective hemispheres during the late winter and spring months (Townsend, 1935) but the species was not recorded in the sheltered waters of the Great Barrier Reef. Paterson & Paterson (1984) considered that the Americans avoided the region because of its dangerous waters and its relative shallowness precluded the presence of sperm whales, a prime quarry of 19th century whalers.
Although the findings of the present study support the opinions of Paterson & Paterson (1984) and Simmons & Marsh (1986) that Great Barrier Reef waters in the vicinity of latitude 20 ° S are an important calving ground for the east Australian humpback whale stock, there is accumulating evidence that occasional calving occurs at higher latitudes in east Australian waters (Table 3). The tendency of humpback whale mother/calf pairs to continue migrating northwards after calving had occurred at a relatively high latitude was noted by Chittleborough (1965).
Humpback whales in Australian waters 41
Fig. 5.
2o*__s 2o,s
2 5o_~s 2 5 0 S
y 'Oos 3 5 " S 3 5 ° S
0 t 40°__S 6 t 40°._ S
, -
I I ~1 loEs ~1 °1 ~,1
15~.°S 15*S
,o._= - , ~ , r ~ - % ,o-s J I%
2s~s
July
3o_~ s
A u g u s t
o ~ 40°. S o
w~ow , w ~ , w o a o
t 25o_._ S
30°_S
35"__s
4o°._.._s
Dispersal of humpback whales along the east Australian coast from May to August (1983-1987). O, Northbound; m, southbound; &, non-directional.
Fig. 6. Dispersal of humpback whales along the east Australian coast from September to December (1983-1987). O, Northbound; m, southbound; &, non-directional.
Humpback whales in Australian waters
TABLE 3 Humpback Whales Accompanied by Recently Born Calves Seen
Migrating Northwards Past Cape Moreton/Point Lookout
43
Date Reference
30 August 1982 27 June 1984 11 July 1985 5 October 1985 7 July 1986 29 July 1986 30 September 1987
Paterson & Paterson (1984) Paterson (1985) Paterson (1986) Paterson (1986) G. D. Kaufman & M. Osmond (pers. comm.) G. D. Kaufman & M. Osmond (pers. comm.) Present study
Another eye-witness account of humpback whale calving was reported from Rooney Point (24 ° 49' S, 153 ° 07' E) at the north-eastern entrance to Hervey Bay (Paterson, 1985). Assemblage of large numbers of southbound humpback whales in the Hervey Bay region during mid-September was reported by Paterson (1982).
By late November most humpback whales have left the east Australian coast (Fig. 6) en r o u t e to the summer feeding grounds in Antarctic waters. Dawbin (1966) noted humpback whale feeding activity during the southern migration between latitudes 35 ° and 46 ° S on the New Zealand coast. Similar activity was observed during late October and early November in 1986 at latitude 37°S on the east Australian coast (Paterson, 1987). Behaviour considered to be associated with mating has also been observed at that latitude during October and November (Paterson, 1984a). Overlap between feeding and mating has been reported from much higher latitudes. Nishiwaki & Hayashi (1950) observed a prolonged period of humpback whale mating at latitude 65 ° S, just north of the Balleny Islands, on 13 January 1948.
Small numbers of humpback whales have been observed in Great Barrier Reef waters between late November and early February (Paterson & Paterson, 1984; Simmons & Marsh, 1986; Paterson, 1987) including some near Murray Island (latitude 10 ° 31' S) at the northern end of the Reef. As indicated by Simmons & Marsh (1986), it is possible that those seen east of Murray Island had not traversed the waters inside the Reef. Their migratory route remains undetermined but it is possible that they and a group of three, including a calf, seen outside the Reef at 17 ° 01' S, 146 ° 50' E on 30 January 1987 comprised part of the Area V (130 ° E-170 ° W) humpback whale stock which migrates through the Coral Sea and passes Norfolk Island (Slijper, 1962).
44 Robert Paterson, Patricia Paterson
TABLE 4 Northbound Humpback Whales Seen per 100 Hours of Observation in the Vicinity of Latitude 27 ° S on the East Australian Coast in 1961/62, 1981/82
and 1986/87
Observation Relation to Sightings period whaling operations per 100 h
Penultimate whaling year 88.2 Final whaling year 38"6 19 years post-whaling 48.2 20 years post-whaling 58-5 24 years post-whaling 74.2 25 years post-whaling 65'3
PRESENT STATUS
The Area V humpback whale stock has no fewer than three calving grounds; the east Australian coast, the Coral Sea and the Tongan region (Slijper, 1962). This study does not include any opinion as to the status of humpback whales in the latter two regions.
The data from 1983-87 (Table 1) and 1981-82 (Paterson & Paterson, 1984) are comparable with those of Chittleborough (1965) obtained at the same latitude in 1961-62, with the following qualifications. Our observations were made from elevated shore positions whereas the earlier ones were made from whale-chasers, assisted by an aircraft in 1962. Because humpback whales migrate close to the shore at this latitude (Chittleborough, 1965; Dawbin, 1966; Bryden, 1985) it is likely that the majority passing in daylight were within visible range of both the 1961-62 and 1981-87 observers.
Chittleborough (1965) combined the weekly sighting data for the peak period of the northern migration in 1961-62 and those are shown with the comparable data from 1981-82 and 1986-87 in Table 4. (The lower sighting rate in 1987 compared with 1986 may have resulted from a longer observation period which included the decline phase of the northern migration. The rate for the period 15 June-25 July 1987 was 74.8 per 100 h.) The data indicate that the east Australian humpback whale stock, after a 25- year respite from exploitation, has recovered from the low numbers recorded in 1962 but has not yet reached 1961 numbers.
RATE OF RECOVERY
As the observations were made by the same persons at the same location at approximately the same time of the year, the humpback whale numbers
Humpback whales in Australian waters 45
observed per 10 h may be expected to be a reliable index of the change in stock numbers year by year. There are factors, however, which introduce sampling errors, such that even if the stock numbers did not change from year to year, the numbers observed could be expected to vary significantly. Observations were made over a period of four to five weeks encompassing the migration peaks. The period was too short to cover the whole migration and as the actual time of the peaks may vary slightly from year to year (Dawbin, 1966) as well as the rate at which the numbers rise and fall, the observation periods may have covered a different portion of the total stock migrating each year. The numbers of humpback whales observed were also variable on a day-to-day basis, even at or near the peaks, particularly during the southern migration. Variations from fewer than 5 to greater than 15 in daily counts were recorded in some weeks and the exclusion from the observation period of a day when no humpback whales passed would have a significantly different effect on the results than the exclusion of a day when 20 passed.
To determine the average rate of increase in stock numbers between 1981 and 1987, the numbers of humpback whales seen per 10 h (Table l; Paterson & Paterson, 1984) for the northern and southern migrations were averaged each year. As most calving occurs at latitudes lower than 27 ° S, and births exceed deaths in an expanding population, the greatest change in the stock numbers must occur between the northern and southern migrations in any year. Therefore, it would be logical to average the data from the southern migration in one year with those of the northern migration from the next year, if the observations included the full period of the migrations. However, Chittleborough (1965) showed that newborn humpback whale calves pass late in the southern migration (Fig. 4) by which time our observations had usually ceased. Therefore, our data would not show a significant change for the southern migration compared with the preceding northern migration. This is consistent with the data from the extended observation period in 1987 when the average number of humpback whales seen per 10 h during the first 9 weeks of the southern migration (until mid-October) is comparable with that for the first 9 weeks of the northern migration, whereas the numbers for the 11 weeks to the end of October are approximately 10% higher than for the first 11 weeks of the northern migration.
The average numbers of humpback whales seen per 10h in each year between 1981 and 1987 are shown in Fig. 7 and are plotted on a logarithmic scale so that a constant rate of increase will appear as a straight line on the graph. The linear regression line on the logarithms of the data was calculated by the method of least squares and is also shown. The slope of the line shows an average rate of increase of 9-7% with a correlation coefficient of 0-96. The 95% confidence interval lies between 6% and 13%. The standard deviation of the points from the regression line gives the standard error of estimate of
(n 1 0 i I i i I I I I i W --,I
46 Robert Paterson, Patricia Paterson
~<~ 8 RL
I •
4 F--
r a m 3
z I I I I I I I I 1 1980 82 84 86 88
Y E A R
Fig. 7. Number of humpback whales seen per 10h as the average of the northern and southern migrations each year between 1981 and 1987. RL indicates the regression line
calculated using the logarithm of the number of humpback whales per l0 h.
6"4% of the value given by the line for the data averaged over both migrations. When the northern and southern migration data are considered separately the standard errors are 14% and 9% respectively. The results illustrate the difficulty of obtaining a reliable estimate of the rate of increase in a stock such as this, since the sampling errors as a percentage of the numbers counted are comparable to the annual rate of increase. Thus several consecutive years of observation are required to obtain a reliable estimate.
STOCK SIZE
The extended observations in 1987 appear to cover almost all the northern migration and the majority of the southern migration and should be suitable to estimate stock numbers. Both migrations commence abruptly but taper gradually (Fig. 2). The following assumptions have been made.
(1) Humpback whales are equally likely to pass during the night as during the day.
(2) The likelihood of sighting humpback whales actually passing is constant throughout the hours of daylight.
(3) All humpback whales pass close enough to the shore to be seen. (4) All humpback whales passing during the observation periods are
seen, irrespective of variations in visibility.
Humpback whales in Australian waters 47
(5) The numbers of nor thbound humpback whales passing before and after the five months of observation were a sufficiently small proport ion of the total to be negligible.
Assumption (1) is supported by the data of Bryden (1985) and (2) can be tested by the data in Fig. 3, which shows the numbers of humpback whale groups sighted between 1983 and 1987, as a function of time of day when they were first seen. The sighting rate shows little variation between 0800 and 1600 h but substantial variation early and late in the day. However, the average of 75 groups h -1 for the period 050(O800h and 1600-1800h is sufficiently close to the average of 72 h-1 from 0800 to 1600 h to indicate that the variation averages out and assumption (2) is acceptable. The remaining assumptions will result in a small underestimate of numbers (Bryden, 1985).
The stock size was estimated by summing the numbers of nor thbound humpback whales seen per 10h for each week of observation and multiplying by 24 x 7/10. This gave a total of 1107 for the 22 weeks' observation during the northern migration as the estimate of population for early 1987. The error of this estimate would be substantially less than the standard error obtained in the data used to estimate the regression line, since by observing for 22 weeks--almost the full migrat ion--we avoided the variability evident in the data of earlier years when only four or five weeks near the peak were sampled. By the same method as above, the total number of humpback whales passing in the first 11 weeks of the southern migration (to the end of October) was estimated to be 1057, approximately 10% more than for the first 11 weeks of the northern migration. However, if we consider only the first 8 weeks to exclude that part of the southern migration when most newborn humpback whales are expected to pass, the numbers are similar, 897 during the northern migration and 881 for the southern migration.
Using the same method, the population in early 1961 (Fig. 4) can be estimated, although the sampling methods were different (see above). The result is approximately 1400 and at the present rate of increase our best estimate indicates that this stock number could be reached by about 1990.
A C K N O W L E D G E M ENTS
We owe particular thanks to our colleague Dr D. H. Cato who assisted in the preparation of the estimates of stock size and recovery rate. Numerous persons generously forwarded sighting reports following our annual requests in Australian Fisheries and the editorial staff of that journal are thanked for their many years of cooperation.
48 Robert Paterson, Patricia Paterson
R E F E R E N C E S
Baker, C. S., Herman, L. M., Perry, A., Lawton, W. S., Straley, J. M. & Straley, J. H. (1985). Population characteristics and migration of summer and late-season humpback whales (Megaptera novaeangliae) in southeastern Alaska. Mar. Mammal Sci., 1, 304-23.
Bryden, M. M. (1985). Studies of humpback whales (Megaptera novaeangliae), Area V. In Studies of Sea Mammals in South Latitudes, ed. by J. K. Ling & M. M. Bryden. South Australian Museum, Adelaide, pp. 115-23.
Cato, D. H. (1984). Recording humpback whale sounds off Stradbroke Island. In Focus on Stradbroke, ed. by R. J. Coleman, J. Covacevich & P. Davie, Boolarong, Brisbane, pp. 285-90.
Chittleborough, R. G. (1965). Dynamics of two populations of the humpback whale, Megaptera novaeangliae (Borowski). Aust. J. Mar. Freshwat. Res., 16, 33-128.
Clarke, R. (1954). Open boat whaling in the Azores. The history and present methods of a relic industry. "Discover); Rep., 26, 281-354.
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Durbidge, E. & Covacevich, J. (1981). North Stradbroke Island. Stradbroke Island Management Organisation, Amity Point.
Grady, D. (1982). The Perano Whalers of Cook Strait 1911-1964. A. H. and A. W. Reed, Wellington and Sydney.
Kaufman, G. D., Smultea, M. A. & Forestell, P. (1987). Use of lateral body pigmentation patterns for photographic identifcation of east Australian (Area V) humpback whales. Cetus, 7(1), 5-13.
Nishiwaki, M. & Hayashi, K. (1950). Biological survey of fin and blue whales taken in the Antarctic season 1947-48 by the Japanese fleet. Sci. Rep. Whales Res. Inst., 3, 132-90.
Paterson, R. (1982). 'Whale watch' sightings increase again. Aust. Fish., 41(5), 25-9. Paterson, R. (1984a). Migration patterns of humpback whales (Megaptera
novaeangliae) in the waters adjacent to Moreton and North Stradbroke Islands. In Focus on Stradbroke, ed. by R. J. Coleman, J. Covacevich & P. Davie. Boolarong, Brisbane, pp. 342-7.
Paterson, R. (1984b). More good news on whales. Aust. Fish., 43(5), 34-6. Paterson, R. (1985). Whale numbers increasing. Aust. Fish., 44(5), 43-5. Paterson, R. (1986). Optimistic outlook for east coast humpback whale stock. Aust.
Fish., 45(4), 25-8. Paterson, R. (1987). Recovery in the east Australian humpback whale stock. Aust.
Fish., 46(8), 32-6. Paterson, R. & Paterson, P. (1984). A study of the past and present status of
humpback whales in east Australian waters. Biol. Conserv., 29, 321-43. Simmons, M. L. & Marsh, H. (1986). Sightings of humpback whales in Great Barrier
Reef waters. Sci. Rep. Whales Res. Inst., 37, 31-46. Slijper, E. J. (1962). Whales. Hutchinson, London. Townsend, C. H. (1935). The distribution of certain whales as shown by log book
records of American whaleships. Zoologica, N.Y., 19, 1-50.
