Beaver Reef (2001-2002)

TritonAcanthaster

A preliminary survey of Beaver Reef was conducted during 2001 and 2002. Beaver is a mid-shelf reef off Mission Beach and Dunk Island on the Great Barrier Reef in Australia. Beaver had just experienced it’s third major outbreak of crown-of-thorns starfish (Acanthaster planci) in four decades. The tour operators that visit Beaver have attempted to control the starfish by manual collection and killing in the area of their dive operations.

This relatively small area of starfish control was SCUBA dived regularly and searched repeatedly in detail for the presence of giant tritons. At least six live specimens of giant triton were located during the study. All specimens of any encountered species of starfish were also recorded. The study was continued into 2002 until both crown-of-thorns starfish and giant tritons were once again too difficult to locate. Beaver Reef will be resurveyed for both tritons and starfish, but our focus in 2003 and 2004 will probably have to move further south to John Brewer Reef off Townsville which is presently undergoing a renewed starfish outbreak.

John Brewer Reef was surveyed previously for giant tritons in 1986 and 1988 at the end of the previous outbreak. Until there is further coral regeneration at Beaver Reef, it is expected to carry only a very small population of crown-of-thorns starfish. This population will be spread out looking for food as will their predators the giant triton. At this stage of the outbreak cycle, it is very difficult to locate tritons. This was the case at John Brewer Reef in 1989 and Norman, Hastings and Saxon Reefs in 1990. We were unable to fund the ultrasonic tags that would have enabled us to continue the monitoring of tritons at Beaver Reef subsequent to the starfish outbreak. We are now hoping to conduct a series of starfish bait experiments which if successful, will provide a means of studying the giant triton on a reef between crown-of-thorns starfish outbreaks.

Beaver Reef (Feeding Data 2001-2002)

#

DATE

ID

DIET

COMMENT

1

05/04/2001 1,2,3 Nil Shark Alley, 3 tritons in 15m – Mike, Andy, John, Norm

2

28/08/2001 1 Nil Friendship Bombie, triton in 10m – Col, John

3

10/09/2001 2 Nil Friendship Wall, triton in 1 m – John

4

09/10/2001 3 Nil Triton on cage with Acanthaster – Tourist

5

10/10/2001 3 Nil Triton not hungry – Darren

6

11/10/2001 3 Acanthaster planci (adult) Devoured instantly – AM SHAL, 20 LL, 7 FE, NP

7

12/10/2001 3 Acanthaster planci (adult) Starfish injured – AM FRBO, AP, 10 LL; PM SHAL, AP, 20 LL, 2 FE

8

15/10/2001 3 Nil Not hungry – AM SITE1, AP, 2 LL, NR, 2 FE; PM FRBO, 20 LL, CN, 2 FE

9

16/10/2001 3 Nil Not hungry – AM SITE1, AP, 3 LL; PM FRBO, 20 LL, GW

10

20/10/2001 3 Nil Not hungry – AM SITE1, AP, LL, 2 NN, 2 FE; PM SHAL, 12 LL, NP, FM, 2 FE

11

21/10/2001 3 Linckia laevigata (adult) Devoured instantly – Fernando

12

23/10/2001 3 Acanthaster planci (sub) Devoured instantly – AM FRBO, 2 AP, 2 CN, 20 LL; PM SITE1, LL, NN, FE, NC

13

25/10/2001 3 Nil Not hungry – AM FRBO, AP, 10 LL, FE; PM SITE1, NN, FE

14

27/10/2001 3 Nil Not hungry – AM SITE1, 3 AP, NC; PM SITE1, NR

15

28/10/2001 3 Nardoa pauciforis Devoured instantly – AM NCAY, 3 AP, 4 LL, NP, FE; PM SITE1, FE

16

29/10/2001 3 Acanthaster planci Devoured instantly – PM NOWA-SHAL, AP, 4 LL, NN

17

30/10/2001 3 Nil Not hungry – AM NCAY AP, LL, NP, NR, FE, EL

18

31/10/2001 3 Acanthaster planci Devoured instantly – AM SITE1, AP, 2 LL, FE; PM SHAL, 4 LL, NP, 2 FE

19

01/11/2001 3 Nil Not hungry – AM SITE1, FE; PM NOWA, 4 FE

20

03/11/2001 3 Nil In cave. AM MOBO NIL, PM WEBO NIL

21

04/11/2001 4 Linckia laevigata Bombie off Friendship Wall, triton in 3m – Fernando

22

06/11/2001 3 Nil Not hungry

23

06/11/2001 4 Acanthaster planci Devoured instantly, AM FEBO, CT, 6 LL; PM NCAY, AP, 25 LL, 6 FE

24

08/11/2001 3 Nil Not hungry

25

08/11/2001 4 Acanthaster planci Devoured instantly, AM NCAY, 2 AP, 10 LL, FE; FRWA, 20 LL, FE

26

10/11/2001 3 Nil Regurgitated AP spines, attacked AP

27

10/11/2001 4 Nil Attacked AP, AM NGUT, AP, 20LL, NN, NP, 2 FE; PM FRBO, AP, 10LL, FE

28

12/11/2001 3,4 Nil Both shells high in cave – Susie

29

15/11/2001 3,4 Nil Both shells high in cave – Susie

30

17/11/2001 3,4 Nil Both shells in cave – Susie

31

19/11/2001 3,4 Acanthaster planci Both shells attacked and consumed prey instantly

32

22/11/2001 3 Acanthaster planci Devoured instantly, SITE1 AP

33

22/11/2001 4 Acanthaster planci Regurgitated Acanthaster planci spines

34

24/11/2001 3 Acanthaster planci Sub-adult devoured instantly. SITE1 3LL, NN, FE

35

24/11/2001 4 Nardoa novaecaledoniae Devoured instantly. Moved 10M

36

25/11/2001 3 Nil High in cave. NCAY, AP, 25LL, 2NN, NP, 4FE

37

25/11/2001 4 Linckia laevigata Devoured instantly

38

25/11/2001 5 Nil Bombie near boat, triton in 2m – Susie

39

25/11/2001 5 Fromia indica Devoured instantly

40

25/11/2001 5 Acanthaster planci Sub-adult devoured instantly 30 minutes after Fromia was eaten

41

27/11/2001 3 Nil Attacked AP, FRBO 3AP, 20LL, 2FE

42

27/11/2001 4 Nil Attacked AP

43

27/11/2001 5 Acanthaster planci Devoured instantly

44

28/11/2001 3 Nil AP in bag eaten. SITE1 APJ, 2FE

45

28/11/2001 4 Acanthaster planci Scraps from bag only

46

28/11/2001 5 Nil Not hungry

48

29/11/2001 3 Acanthaster planci Sub-adult. SITE1 APS, EL, FE

50

29/11/2001 4 Not hungry In crevice

51

29/11/2001 5 Not hungry Moved 1m

52

01/12/2001 3 Nil Missing, SITE1 APS, 2LL, 2FE; FRWA 2AP, 10LL, 2FE

53

01/12/2001 4 Acanthaster planci Sub-adult devoured instantly

54

01/12/2001 5 Nil Attacked AP instantly

55

02/12/2001 3 Nil Missing, FRBO 2AP, 25LL, FE; SHAL-WCAY AP, 15LL, 2FE, 2EL

56

02/12/2001 4 Nil Not hungry

57

02/12/2001 5 Nil Not hungry

58

03/12/2001 3 Nil Missing

59

03/12/2001 4 Acanthaster planci Devoured instantly

60

03/12/2001 5 Nil Not hungry

61

06/12/2001 3 Nil Missing

62

06/12/2001 4 Nil In crevice

63

09/12/2001 3,4 Nil Missing

64

09/12/2001 5 Acanthaster planci Devoured instantly. SITE1 FE; FRWA 15LL

65

10/12/2001 3,4 Nil Missing, NCAY 3FE, NO; FRBO 10LL, 2FE

66

10/12/2001 5 Neoferdina offreti Devoured instantly

68

11/12/2001 3,4 Nil Missing, FRBO 15LL, FE; SITE1 APS, 2FE

69

11/12/2001 5 Acanthaster planci Sub-adult devoured instantly

70

12/12/2001 3,4 Nil Missing, SITE1 AP; FRWA 15LL, 2FE. LM

71

12/12/2001 5 Acanthaster planci Devoured instantly

72

13/12/2001 5 Nil Moved 1m, NCAY 15LL, 2NN, 2NP, FE, EL

74

13/12/2001 ES1 Nil Observed previously on NOWA

75

13/12/2001 ES2 Nil Recently died. Operculum located. 1-2months internal growth of algae..

76

16/12/2001 3,4 Nil Missing, NOWA FE; FRWA AP, 10LL, FE

77

16/12/2001 5 Acanthaster planci Devoured instantly

78

17/12/2001 3,4 Nil Missing, SITE1 NO, FRWA APS, 20LL, NN

79

17/12/2001 5 Nil Not hungry

80

18/12/2001 3 Nil Missing, FRBO 20LL, 2FE, 2NR; SITE1 AP, FE

81

18/12/2001 4 Nil Moved 30M

82

18/12/2001 4 Acanthaster planci Devoured instantly

83

18/12/2001 5 Nil Not hungry

84

20/12/2001 3,4 Nil Missing

85

20/12/2001 5 Nil Not hungry, NCAY 30LL, NN, 2FE; SITE1 APS, FE

86

22/12/2001 3 Nil Moved 30M, SITE1 4APS, LL

87

22/12/2001 3 Acanthaster planci Devoured sub-adult instantly

88

22/12/2001 4 Acanthaster planci Devoured sub-adult instantly, Moved 20M

89

22/12/2001 5 Acanthaster planci Devoured sub-adult instantly

90

23/12/2001 3 Nil Missing, NCAY 2AP, 6LL, FE; SITE1 LL, FE, EL

91

23/12/2001 4 Acanthaster planci Devoured instantly

92

23/12/2001 5 Acanthaster planci Devoured instantly

93

24/12/2001 3 Nil Missing, FRBO-NOWA APS, 5LL, FE

94

24/12/2001 4 Nil Moved 2M

95

24/12/2001 5 Acanthaster planci Sub-adult devoured instantly

96

27/12/2001 3 Nil Missing, SITE1-BOAT 5LL, LM, 2FE; FRBO 20LL, 3FE

97

27/12/2001 4 Nil Unmoved

98

27/12/2001 5 Nil Unmoved

99

28/12/2001 3 Nil Missing, SITE1 NN, NP, 2FE, EL; NWCAY AP, 100LL, NN, NP, EL

100

28/12/2001 4 Nil Not hungry

101

28/12/2001 5 Acanthaster planci Devoured instantly

102

29/12/2001 3 Nil Missing, NCAY 2AP, 30LL, 2NN, NP, 5FE; NECAY 10LL, FE; NWCAY APS, 50LL, NN, 4FE

103

29/12/2001 4 Acanthaster planci Devoured after 5 mins

104

29/12/2001 5 Nil Not hungry

105

30/12/2001 3 Nil Missing, FRBO AP, 10LL, NN, 3FE, CN; SHAL-WCAY 20LL, NN, NR, 3FE

106

30/12/2001 4 Nil Not hungry

107

30/12/2001 5 Nil Not hungry

108

30/12/2001 6 Nil 150m west of NOWA, triton in 2m – Col, John

109

31/12/2001 4 Culcita novaeguineae Attached itself and fed

110

31/12/2001 5 Nil Not hungry

111

31/12/2001 6 Acanthaster planci Regurgitated large number of spines

112

31/12/2001 6 Acanthaster planci Devoured instantly

113

03/01/2002 4 Nil Unmoved

114

03/01/2002 5 Nil Unmoved, SITE1 Nil; FRWA 2APJ, 15LL, 2NN, FM

115

03/01/2002 6 Nil Unmoved

116

04/01/2002 4 Nil Moved 2m, NCAY ES3, 10LL, 2FE; SHAL ES4, 10LL, 3FE

117

04/01/2002 5 Culcita novaeguineae Attached itself and fed

118

04/01/2002 6 Nil Unmoved

119

04/01/2002 ES3 Nil Dead shell, 50m north of cay recently crushed

120

04/01/2002 ES4 Nil Dead shell, SHAL 10m, clean and intact

121

05/01/2002 4 Culcita novaeguineae Attached itself and fed

122

05/01/2002 5 Nil Unmoved, NCAY-NWCAY 75LL, 2FE

123

05/01/2002 6 Nardoa novaecaledoniae Devoured instantly

124

06/01/2002 4 Nil Unmoved, NCAY-NWCAY 75LL, 2NN, NP, 5FE

125

06/01/2002 5 Culcita novaeguineae Feeding on remains

126

06/01/2002 6 Nardoa novaecaledoniae Devoured instantly

127

08/01/2002 4 Nardoa novaecaledoniae Devoured instantly, NCAY 50LL, 2NN, 5FE; FRBO 20LL, 2FE, CN

128

08/01/2002 5 Culcita novaeguineae Feeding on remains

129

08/01/2002 6 Linckia laevigata Attacked instantly – prey removed

130

08/01/2002 6 Culcita novaeguineae Attached itself and fed

131

09/01/2002 4 Linckia laevigata Devoured instantly, NOWA LL, 6FE; SITE1 AC

132

09/01/2002 5 Culcita novaeguineae Attached itself and fed, starfish escaped

133

09/01/2002 6 Nil Unmoved

134

10/01/2002 4 Nil Unmoved, NCAYCR APS, 50LL, 6FE; SITE1 AP, LL, NO

135

10/01/2002 5 Nil Unmoved,

136

10/01/2002 6 Nil Unmoved,

137

12/01/2002 4 Nil Not hungry, moved 3m, NOWA LL, 5FE; SITE1 AP, FRBO 7LL, NN

138

12/01/2002 5 Nil Not hungry

139

12/01/2002 6 Acanthaster planci Devoured sub-adult instantly, moved 2m

140

13/01/2002 4 Nil Not hungry, SITE1 LL, AP; NCAY-NWCAY 75LL, NP, FE

141

13/01/2002 5 Nil Not hungry

142

13/01/2002 6 Nardoa novaecaledoniae Devoured instantly

143

13/01/2002 6 Acanthaster planci Regurgitated Nardoa then fed on mashed Acanthaster

Charonia Research wishes to thank Quick Cat Cruises, Quick Cat Dive and Quick Cat Scuba Adventures of Mission Beach for their logistic support. Without this in-kind support, preliminary studies such as these, could never be initiated. For further details about how you can be involved in this project please Email and state your details together with any particular areas of interest or concern.