3.2 sampling sites and habitats - department of the...
TRANSCRIPT
Final Report 101
3.2 Sampling sites and habitats
Alan Williams, Gordon Keith, Bruce Barker
3.2.1 Acoustic multibeam maps
An overview of the navigation track (Fig. 3.2.1.1) shows the sampling sites
identified by site number (as used by Roberts & Clark 2006) and by vessel data
base number against a backdrop of bathymetry from Harris et al. (2003). Pre-
existing broadscale bathymetry was used to guide choice of sampling sites,
where multibeam (swath) acoustic data were collected and mapped up in real
time at sea to provide the basis for selecting sampling stations (Figs. 3.2.1.2 to
15). We found that the broadscale bathymetry was highly useful for guidance
on the general topography of the region; however it was not always accurate at
the scale of sampling sites (e.g. Fig 3.2.1.4 or Fig 3.2.1.7). Details of the
acoustic data held in Australia by CSIRO Marine Research are provided below.
NORFANZ acoustic data holdings
A copy of the acoustic data holdings for the NORFANZ cruise is stored online
at the CSIRO Marine Laboratories in Hobart on a server:
beam:/beta/data/gx30_NORFANZ.
This includes data from the EM300 swath mapper and the ES60 single beam
echosounder.
Raw swath data
Swath data exists in the swath/raw data directory for the following surveys:
Final Report 102
lhr, lhr2, lhr3, lhr4, nnr, nnr2, snr, transit1, transit2, wnr, wnr2, wnr3, wnr4, wnr5
For each survey we have the EM300 raw data files. The sound velocity profiles
used are in the swath/processed/em300/soundvel directory. There is a total of
4 gigabytes of raw EM300 data.
Processed swath data
TIFF images
The directory swath/processed/em300/proc contains TIFF images for each of:
bs – backscatter (grey scale)
dtm – digital terrain model (sun illuminated coloured bathymetry)
ele – elevation model (very dark images)
for each of the following areas:
lhr10 lhr7 lhr8 lhr9 nnr4 nnr5 nnr6 snr2 snr3 wnr11 wnr12 wnr13 wnr14 wnr15.
Each tiff file has an associated TIFF world files (.tfw) for a mercator 41 degree
projection with origin at 100 degrees east.
Ship track
The vessel track of the logged swath data is available as a
shape file in swath/processed/em300/multibea.shp.
Final Report 103
Charts
PDF files of charts showing coloured bathymetry shaded with backscatter are
located in the swath/processed/underway directory.
Underway data
Underway data for the voyage is held in a text file in the
swath/processed/underway directory with the following format:
Column Value Description
1 Date GP500 Syncronized date YYYYMMDD == NZST
2 Time GP500 time HHMM SS == NZST
3 Lat GP500 Latitude, -S, +N
4 Long GP500 Longitude +E, -W
5 D1 EK500 Depth 1
6 D2 EK500 Depth 2
7 D3 EK500 Depth 3
8 D4 KMC 2000 Depth - 38KHz
9 Temp Sea Surface Temperature
10 Sal Sea Surface Salinity
11 U_Time GP500 Time - of secs since 1/1/1970 GMT
ES60 single beam sounder
ES60 data for the voyage is located in the ES60_data/ek5_format directory.
There are 666 MB of data in EK5 format, made up of 134 files of 5MB each.
104 Final Report
Fig.
3.2
.1.1
Ove
rvie
w o
f the
nav
igat
ion
trac
k w
ith th
e ta
rget
ed s
ites
iden
tifie
d by
site
num
ber a
nd b
y ve
ssel
dat
a ba
se n
umbe
r fol
low
ing
Rob
erts
and
Cla
rk (2
006)
. Not
e th
at S
ite 1
0 is
situ
ated
on
the
Wes
t Nor
folk
Rid
ge (W
NR
), de
spite
the
mis
lead
ing
data
bas
e la
bel o
f LH
R-1
5.
Bat
hym
etry
con
tour
s fro
m H
arris
et a
l. (2
003)
Final Report 105
(ver
tical
exa
gger
atio
n 5x
; Bat
hym
etry
co
ntou
rs: H
arris
et a
l., 2
003)
Fig.
3.2
.1.2
Mul
tibea
m s
onar
(‘sw
ath’
) map
of s
ampl
e si
te 1
(Sou
th N
orfo
lk R
idge
= S
NR
) sho
win
g lo
catio
n of
sam
ple
stat
ions
So
uth
Nor
folk
Rid
ge
TOT.
O
RH
-Tra
wl
Rat
catc
her
Beam
Traw
l N
IWA
sled
She
rman
sl
edR
ock
dred
ge
Pipe
dred
ge
MW
T fin
e m
esh
cod
end
Ben
thos
cam
era
CTD
# sa
mpl
es (i
n br
acke
ts: n
o ca
tch)
8
3
5
2 1
106 Final Report
(ver
tical
exa
gger
atio
n 5x
; Bat
hym
etry
co
ntou
rs: H
arris
et a
l., 2
003)
Fig.
3.2
.1.3
Mul
tibea
m s
onar
(‘sw
ath’
) map
of s
ampl
e si
te 2
(Sou
th N
orfo
lk R
idge
= S
NR
) sho
win
g lo
catio
n of
sam
ple
stat
ions
So
uth
Nor
folk
Rid
ge
TOT.
O
RH
-Tra
wl
Rat
catc
her
Beam
Traw
l N
IWA
sled
She
rman
sl
edR
ock
dred
ge
Pipe
dred
ge
MW
T fin
e m
esh
cod
end
Ben
thos
cam
era
CTD
# sa
mpl
es (i
n br
acke
ts: n
o ca
tch)
9
(1)
4
1
4 (1
)
1
Final Report 107
(ver
tical
exa
gger
atio
n 5x
; Bat
hym
etry
co
ntou
rs: H
arris
et a
l., 2
003)
Fig.
3.2
.1.4
Mul
tibea
m s
onar
(‘sw
ath’
) map
of s
ampl
e si
te 3
(Nor
folk
Rid
ge p
rope
r = N
NR
) sho
win
g lo
catio
n of
sam
ple
stat
ions
N
orfo
lk R
idge
pro
per
(Not
e sc
ale
bar!)
TO
T.
OR
H-T
raw
l R
atca
tche
rBe
amTr
awl
NIW
Asl
edS
herm
an
sled
Roc
kdr
edge
Pi
pedr
edge
MW
T fin
e m
esh
cod
end
Ben
thos
cam
era
CTD
# sa
mpl
es (i
n br
acke
ts: n
o ca
tch)
9
(2)
3
2 (1
) 3
1
(1)
2
108 Final Report
(ver
tical
exa
gger
atio
n 5x
; Bat
hym
etry
co
ntou
rs: H
arris
et a
l., 2
003)
Fig.
3.2
.1.5
Mul
tibea
m s
onar
(‘sw
ath’
) map
of s
ampl
e si
te 4
(Nor
folk
Rid
ge p
rope
r = N
NR
) sho
win
g lo
catio
n of
sam
ple
stat
ions
N
orfo
lk R
idge
pro
per
(Not
e sc
ale
bar!)
TO
T.
OR
H-T
raw
l R
atca
tche
rBe
amTr
awl
NIW
Asl
edS
herm
an
sled
Roc
kdr
edge
Pi
pedr
edge
MW
T fin
e m
esh
cod
end
Ben
thos
cam
era
CTD
# sa
mpl
es (i
n br
acke
ts: n
o ca
tch)
10
(1)
5 (1
)
3
1 1
1 1
Final Report 109
(ver
tical
exa
gger
atio
n 5x
; Bat
hym
etry
co
ntou
rs: H
arris
et a
l., 2
003)
Fig.
3.2
.1.6
Mul
tibea
m s
onar
(‘sw
ath’
) map
of s
ampl
e si
te 5
(Nor
folk
Rid
ge p
rope
r = N
NR
) sho
win
g lo
catio
n of
sam
ple
stat
ions
Nor
folk
Rid
ge p
rope
rTO
T.
OR
H-T
raw
l R
atca
tche
rBe
amTr
awl
NIW
Asl
edS
herm
an
sled
Roc
kdr
edge
Pi
pedr
edge
MW
T fin
e m
esh
cod
end
Ben
thos
cam
era
CTD
# sa
mpl
es (i
n br
acke
ts: n
o ca
tch)
5
(1)
2
1
2 (1
)
1 1
110 Final Report
(ver
tical
exa
gger
atio
n 5x
; Bat
hym
etry
co
ntou
rs: H
arris
et a
l., 2
003)
Fig.
3.2
.1.7
Mul
tibea
m s
onar
(‘sw
ath’
) map
of s
ampl
e si
te 6
(Lor
d H
owe
Ris
e =
LHR
) sho
win
g lo
catio
n of
sam
ple
stat
ions
Lord
How
e R
ise
TOT.
O
RH
-Tra
wl
Rat
catc
her
Beam
Traw
l N
IWA
sled
She
rman
sl
edR
ock
dred
ge
Pipe
dred
ge
MW
T fin
e m
esh
cod
end
Ben
thos
cam
era
CTD
# sa
mpl
es (i
n br
acke
ts: n
o ca
tch)
8
(2)
2 (2
)
2
4
1 1
Final Report 111
(ver
tical
exa
gger
atio
n 5x
; Bat
hym
etry
co
ntou
rs: H
arris
et a
l., 2
003)
Fig.
3.2
.1.8
Mul
tibea
m s
onar
(‘sw
ath’
) map
of s
ampl
e si
te 7
(Lor
d H
owe
Ris
e =
LHR
) sho
win
g lo
catio
n of
sam
ple
stat
ions
Lord
How
e R
ise
TOT.
O
RH
-Tra
wl
Rat
catc
her
Beam
Traw
l N
IWA
sled
She
rman
sl
edR
ock
dred
ge
Pipe
dred
ge
MW
T fin
e m
esh
cod
end
Ben
thos
cam
era
CTD
# sa
mpl
es (i
n br
acke
ts: n
o ca
tch)
8
(1)
4
4 (1
)
1
112 Final Report
(ver
tical
exa
gger
atio
n 5x
; Bat
hym
etry
co
ntou
rs: H
arris
et a
l., 2
003)
Fig.
3.2
.1.9
Mul
tibea
m s
onar
(‘sw
ath’
) map
of s
ampl
e si
te 8
(Lor
d H
owe
Plat
eau
= LH
P) s
how
ing
loca
tion
of s
ampl
e st
atio
ns
Lord
How
e Pl
atea
u (N
ote
scal
e ba
r!)
TOT.
O
RH
-Tra
wl
Rat
catc
her
Beam
Traw
l N
IWA
sled
She
rman
sl
edR
ock
dred
ge
Pipe
dred
ge
MW
T fin
e m
esh
cod
end
Ben
thos
cam
era
CTD
# sa
mpl
es (i
n br
acke
ts: n
o ca
tch)
7
2 2
3
1
Final Report 113
(ver
tical
exa
gger
atio
n 5x
; Bat
hym
etry
co
ntou
rs: H
arris
et a
l., 2
003)
Fig.
3.2
.1.1
0 M
ultib
eam
son
ar (‘
swat
h’) m
ap o
f sam
ple
site
9 (L
ord
How
e Pl
atea
u =
LHP)
sho
win
g lo
catio
n of
sam
ple
stat
ions
Lord
How
e Pl
atea
uTO
T.
OR
H-T
raw
l R
atca
tche
rBe
amTr
awl
NIW
Asl
edS
herm
an
sled
Roc
kdr
edge
Pi
pedr
edge
MW
T fin
e m
esh
cod
end
Ben
thos
cam
era
CTD
# sa
mpl
es (i
n br
acke
ts: n
o ca
tch)
11
4
3 2
2
1
1
114 Final Report
(ver
tical
exa
gger
atio
n 5x
; Bat
hym
etry
co
ntou
rs: H
arris
et a
l., 2
003)
Fig.
3.2
.1.1
1 M
ultib
eam
son
ar (‘
swat
h’) m
ap o
f sam
ple
site
10
(Wes
t Nor
folk
Rid
ge =
WN
R) s
how
ing
loca
tion
of s
ampl
e st
atio
ns
Wes
t Nor
folk
Rid
ge
(Wan
gane
lla B
ank
regi
on)
TOT.
O
RH
-Tra
wl
Rat
catc
her
Beam
Traw
l N
IWA
sled
She
rman
sl
edR
ock
dred
ge
Pipe
dred
ge
MW
T fin
e m
esh
cod
end
Ben
thos
cam
era
CTD
# sa
mpl
es (i
n br
acke
ts: n
o ca
tch)
16
(1)
3 7
(1)
4
2
1
Final Report 115
(ver
tical
exa
gger
atio
n 5x
; Bat
hym
etry
co
ntou
rs: H
arris
et a
l., 2
003)
Fig.
3.2
.1.1
2 M
ultib
eam
son
ar (‘
swat
h’) m
ap o
f sam
ple
site
11
(Wes
t Nor
folk
Rid
ge =
WN
R) s
how
ing
loca
tion
of s
ampl
e st
atio
ns
Wes
t Nor
folk
Rid
geTO
T.
OR
H-T
raw
l R
atca
tche
rBe
amTr
awl
NIW
Asl
edS
herm
an
sled
Roc
kdr
edge
Pi
pedr
edge
MW
T fin
e m
esh
cod
end
Ben
thos
cam
era
CTD
# sa
mpl
es (i
n br
acke
ts: n
o ca
tch)
11
4
3 2
2
1
116 Final Report
(ver
tical
exa
gger
atio
n 5x
; Bat
hym
etry
co
ntou
rs: H
arris
et a
l., 2
003)
Fig.
3.2
.1.1
3 M
ultib
eam
son
ar (‘
swat
h’) m
ap o
f sam
ple
site
12
(Wes
t Nor
folk
Rid
ge =
WN
R) s
how
ing
loca
tion
of s
ampl
e st
atio
ns
Wes
t Nor
folk
Rid
geTO
T.
OR
H-T
raw
l R
atca
tche
rBe
amTr
awl
NIW
Asl
edS
herm
an
sled
Roc
kdr
edge
Pi
pedr
edge
MW
T fin
e m
esh
cod
end
Ben
thos
cam
era
CTD
# sa
mpl
es (i
n br
acke
ts: n
o ca
tch)
10
(1?)
4
2 1
2
1
(+1)
* 15
Final Report 117
(ver
tical
exa
gger
atio
n 5x
; Bat
hym
etry
co
ntou
rs: H
arris
et a
l., 2
003)
Fig.
3.2
.1.1
4 M
ultib
eam
son
ar (‘
swat
h’) m
ap o
f sam
ple
site
13
(Wes
t Nor
folk
Rid
ge =
WN
R) s
how
ing
loca
tion
of s
ampl
e st
atio
ns
Wes
t Nor
folk
Rid
geTO
T.
OR
H-T
raw
l R
atca
tche
rBe
amTr
awl
NIW
Asl
edS
herm
an
sled
Roc
kdr
edge
Pi
pedr
edge
MW
T fin
e m
esh
cod
end
Ben
thos
cam
era
CTD
# sa
mpl
es (i
n br
acke
ts: n
o ca
tch)
7
2 2
1
2
1 1
118 Final Report
(ver
tical
exa
gger
atio
n 5x
; Bat
hym
etry
co
ntou
rs: H
arris
et a
l., 2
003)
Fig.
3.2
.1.1
5 M
ultib
eam
son
ar (‘
swat
h’) m
ap o
f sam
ple
site
14
(Wes
t Nor
folk
Rid
ge =
WN
R) s
how
ing
loca
tion
of s
ampl
e st
atio
ns
Wes
t Nor
folk
Rid
geTO
T.
OR
H-T
raw
l R
atca
tche
rBe
amTr
awl
NIW
Asl
edS
herm
an
sled
Roc
kdr
edge
Pi
pedr
edge
MW
T fin
e m
esh
cod
end
Ben
thos
cam
era
CTD
# sa
mpl
es (i
n br
acke
ts: n
o ca
tch)
7
(1)
3 2
1
1 (1
)
Final Report 119
3.2.2 Seabed images
An overview of the camera equipment and types of deployments (on the ORH
trawl headline or in vertical-drop mode) is given in the voyage report (Clark et
al. 2003, Appendix 10). The locations of camera deployments are shown in
Figure 3.2.2.1, and selected examples of the seabed terrains sampled are
shown in Figure 3.2.2.2). Representative sub-sets of images from each station
are provided in a series of plates in Appendix 9. Typically either 15 or 30
images are shown from each station (one or two plates); the image sequence
numbers (station_F100000*) shows the order of images along each transect.
Collectively, the imagery shows the seabed at all sites to be a variety of hard,
rugged and complex terrains. Bedrock outcrops were visible at many locations
(e.g. Plate 22, station 153), including many with obvious volcanic origin (e.g.
Plate 5). Bedrock made up most of the visible surface substratum at some
locations, most obviously the more complex geomorphic features sampled with
the drop camera (e.g. Fig. 3.2.2.2d; Plate 6, station 42). Rock outcrops also
existed as relatively small isolated features among sediment plains (e.g.
Plate 3, image 28_F1000028) and were responsible for ‘hooking up’ the trawl
gear on occasions. At some locations, e.g. site 6 on the Lord Howe Rise, it
was difficult to find areas suitable for trawl sampling; here images show why the
OHR trawl net was badly damaged at times (Plate 8, station 59). Other
prevalent terrain types included plains of fine sediment (e.g. Plates10 to 15),
and fields of what appear to be loose cobble-sized rocks (Plate 16).
Images also provide insights into the fine scale distribution of fauna, and
particularly the localised distributions of particular taxa in relation to seabed
120 Final Report
features. For example, at station 53 on the top of a flat topped seamount
(guyot) (Fig. 3.2.2.2d) dense beds of small erect sponges were associated with
small areas of relatively smooth, steeply sloping bottom (Plate 7,
images 53_F1010049-50) while larger erect sponges and small encrusting
forms were observed on rugged boulders and rock edges (Plate 7,
images 53_F1000015-16); many intervening areas of hard bottom supported
no sponges. At station 53, sponges were well represented in catches taken by
the Sherman and NIWA benthic sleds (33 and 20 species respectively).
Fig 3.2.2.1 A map of the study region with bathymetric contours showing operation location and number; camera deployments on the headline of the trawl (green text) and in ‘drop mode”(red text).
2000 m
3000 m 2000 m
1000 m
Final Report 121
(a) (b)
(c) (d)
(e) (f)
Fig 3.2.2.2 Selected zoom-in views of swath map (digital terrain model) images showing the general types of terrains and locations where photographic images of the seafloor were taken with the trawl headline mounted camera (green lines and annotation) and drop camera (red lines and annotation). (a) site 1, SNR; (b) site 1, SNR; (c) site 4, WNR; (d) site 5, NNR; (e) site 6, LHR; (f) site 11, WNR.
122 Final Report
(g) (h)
(i) (j)
(k) (l)
Fig 3.2.2.2 (cont.) Selected zoom-in views of swath map (digital terrain model) images showing the general types of terrains and locations where photographic images of the seafloor were taken with the trawl headline mounted camera (green lines and annotation) and drop camera (red lines and annotation). (g) site 10, WNR; (h) site 10, WNR; (i) site 10, WNR; (j) site 2, SNR; (k) site 13, WNR (l) site 14, WNR