Lobster Settlement Collector Project - …...Lobster Settlement Collector Project Update with 2015...
1
Lobster Settlement Collector Project Update with 2015 Results Tricia Pearo Drew 1 , Shelley Armsworthy², Adam Cook 2 , Cheryl Denton² ¹ Fishermen and Scientists Research Society, PO Box 25125, Halifax, Nova Scotia, B3M 4H4 ² Fisheries and Oceans Canada, 1 Challenger Drive, Dartmouth, NS, B2Y 4A2 Introduction: Since 2007, the collaborative lobster collector project between DFO and the FSRS has been using passive collectors (wire mesh lined cages filled with rocks) to sample young-of-year (YOY) lobster (“settlers”). Collectors can be used to provide annual estimates of lobster settlement, as well as an index of abundance of juvenile lobsters. Methods: Collectors have been deployed in five regions along the coast of Nova Scotia (Map and Table 1), in June and July, at water depths ranging from 3 to 40 metres. Temperatures were also recorded in each region, using VEMCO data loggers. Collectors were set in singles or in trawls, either with surface buoys (False Bay, Whitehead) or without (other sites). All collectors were hauled from mid- October to early November, using a commercial hauler, winch and boom. Results and Discussion: The 2015 results with collectors numbers for all sites are shown in Table 1. In most years, the highest settlement numbers have been in the southwestern areas. Settlement was low in several southwestern sites from 2011 to 2013. These areas saw a large increase in 2014 that was not seen in the eastern areas. In 2015, settlement was down in all areas. Settlement appears to be episodic in several of the sampling areas. Average bottom water temperatures for the 2015 project sites are shown in Fig 2. Acknowledgements: Thanks to all of the fishermen who participated (Kevin D’Eon, Kenneth Newell, Jean Marc D’Eon, Mark Gidney, Mitchell Scott, Travis Chute, David Ferguson, Francy Thomas, Eugene O’Leary and Jamie Delorey). Their skills and knowledge are greatly appreciated. Thanks to personnel from DFO (Amy Glass-Wagner) and GCIFA (Sarah Delorey, Will Rhynold, Jonathan Dort and Harvey George). Thanks also to the Department of Fisheries and Oceans and the Nova Scotia Department of Fisheries and Aquaculture for supporting the project. Fig 2. Average bottom water temperature graphs are shown above for project sites in 2015. Figure 1. Lobster Life Cycle Stage IV Table 1. Collector results for 2015. Region Site Number of collectors Count Number per m² Settlers (<13 mm CL) Lobsters (≥ 13 mm CL) Settlers (<13 mm CL) Lobsters (≥ 13 mm CL) False Bay West (deep) 25 0 19 0 1.36 West (shallow) 25 0 18 0 1.29 Total 50 0 37 0.00 1.32 Whitehead Whitehead 49 0 7 0.00 0.26 Total 49 0 7 0.00 0.26 Lobster Bay Abbotts Harbour Island 25 0 15 0 1.07 Canoe Island 25 7 21 .5 1.5 French Point 15 2 8 .24 .95 Gooseberry Island 15 1 9 .12 1.07 John's Island 30 0 27 0 1.61 Lears Island 18 2 18 .2 1.79 Lobster Island 14 0 7 0 .89 Total 142 12 105 .15 1.32 St. Mary's Bay Big Shoal 21 3 12 .26 1.02 Cherry Valley 20 14 20 1.25 1.79 McCormick’s 18 4 12 .40 1.19 Skinny Shoal 20 9 21 .8 1.88 Total 79 30 65 .68 1.47 All Areas 320 42 214 This update was prepared for the FSRS AGM, February 25, 2016. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 14-Jul-15 21-Jul-15 28-Jul-15 4-Aug-15 11-Aug-15 18-Aug-15 25-Aug-15 1-Sep-15 8-Sep-15 15-Sep-15 22-Sep-15 29-Sep-15 6-Oct-15 13-Oct-15 20-Oct-15 Temperature °C Date Lobster Bay Lobster Collector Temperatures 2015 Lears Island Goosberry Island Abbotts Harbour French Point Canoe Island Johns Island Lobster Island 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 5-Aug-15 12-Aug-15 19-Aug-15 26-Aug-15 2-Sep-15 9-Sep-15 16-Sep-15 23-Sep-15 30-Sep-15 7-Oct-15 14-Oct-15 21-Oct-15 28-Oct-15 4-Nov-15 Temperature °C Date False Bay Lobster Collector Bottom Temperatures 2015 Shallow Deep 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 15-Jun-15 22-Jun-15 29-Jun-15 6-Jul-15 13-Jul-15 20-Jul-15 27-Jul-15 3-Aug-15 10-Aug-15 17-Aug-15 24-Aug-15 31-Aug-15 7-Sep-15 14-Sep-15 21-Sep-15 28-Sep-15 5-Oct-15 Temperature °C Date St. Mary's Bay Lobster Collector Temperatures 2015 Cherry Valley Skinny Shoal Long Beach Big Shoal 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 6-Jul-15 13-Jul-15 20-Jul-15 27-Jul-15 3-Aug-15 10-Aug-15 17-Aug-15 24-Aug-15 31-Aug-15 7-Sep-15 14-Sep-15 21-Sep-15 28-Sep-15 5-Oct-15 12-Oct-15 19-Oct-15 26-Oct-15 Temperature °C Date Whitehead Lobster Collector Temperatures 2015
Transcript of Lobster Settlement Collector Project - …...Lobster Settlement Collector Project Update with 2015...
Lobster Settlement Collector Project Update with 2015 Results
Tricia Pearo Drew1, Shelley Armsworthy², Adam Cook2 , Cheryl Denton²
¹ Fishermen and Scientists Research Society, PO Box 25125, Halifax, Nova Scotia, B3M 4H4
² Fisheries and Oceans Canada, 1 Challenger Drive, Dartmouth, NS, B2Y 4A2
Introduction: Since 2007, the collaborative lobster collector project
between DFO and the FSRS has been using passive collectors (wire
mesh lined cages filled with rocks) to sample young-of-year (YOY)
lobster (“settlers”). Collectors can be used to provide annual estimates
of lobster settlement, as well as an index of abundance of juvenile
lobsters.
Methods: Collectors have been
deployed in five regions along the
coast of Nova Scotia (Map and Table
1), in June and July, at water depths
ranging from 3 to 40 metres.
Temperatures were also recorded in
each region, using VEMCO data
loggers. Collectors were set in
singles or in trawls, either with
surface buoys (False Bay,
Whitehead) or without (other sites).
All collectors were hauled from mid-
October to early November, using a
commercial hauler, winch and boom.
Results and Discussion: The 2015 results with collectors numbers
for all sites are shown in Table 1. In most years, the highest settlement
numbers have been in the southwestern areas. Settlement was low in
several southwestern sites from 2011 to 2013. These areas saw a
large increase in 2014 that was not seen in the eastern areas. In 2015,
settlement was down in all areas. Settlement appears to be episodic in
several of the sampling areas. Average bottom water temperatures for
the 2015 project sites are shown in Fig 2.
Acknowledgements: Thanks to all of the
fishermen who participated (Kevin D’Eon,
Kenneth Newell, Jean Marc D’Eon, Mark
Gidney, Mitchell Scott, Travis Chute,
David Ferguson, Francy Thomas,
Eugene O’Leary and Jamie Delorey).
Their skills and knowledge are greatly
appreciated. Thanks to personnel from
DFO (Amy Glass-Wagner) and GCIFA
(Sarah Delorey, Will Rhynold, Jonathan
Dort and Harvey George). Thanks also to
the Department of Fisheries and Oceans
and the Nova Scotia Department of
Fisheries and Aquaculture for supporting
the project.
Fig 2. Average bottom water temperature graphs are shown above for project
sites in 2015.
Figure 1. Lobster Life Cycle
Stage IV
Table 1. Collector results for 2015.
Region Site
Number of
collectors
Count Number per m²
Settlers (<13 mm CL)
Lobsters (≥ 13 mm CL)
Settlers (<13 mm CL)
Lobsters (≥ 13 mm CL)
False Bay West (deep) 25 0 19 0 1.36
West (shallow) 25 0 18 0 1.29
Total 50 0 37 0.00 1.32
Whitehead Whitehead 49 0 7 0.00 0.26
Total 49 0 7 0.00 0.26
Lobster Bay
Abbotts
Harbour Island 25 0 15 0 1.07
Canoe Island 25 7 21 .5 1.5
French Point 15 2 8 .24 .95
Gooseberry
Island 15 1 9 .12 1.07
John's Island 30 0 27 0 1.61
Lears Island 18 2 18 .2 1.79
Lobster Island 14 0 7 0 .89
Total 142 12 105 .15 1.32
St. Mary's
Bay Big Shoal 21 3 12 .26 1.02
Cherry Valley 20 14 20 1.25 1.79
McCormick’s 18 4 12 .40 1.19
Skinny Shoal 20 9 21 .8 1.88
Total 79 30 65 .68 1.47
All Areas 320 42 214
This update was prepared for the FSRS AGM, February 25, 2016.
0123456789
1011121314151617181920
14
-Ju
l-1
5
21
-Ju
l-1
5
28
-Ju
l-1
5
4-A
ug-
15
11
-Au
g-1
5
18
-Au
g-1
5
25
-Au
g-1
5
1-S
ep
-15
8-S
ep
-15
15
-Se
p-1
5
22
-Se
p-1
5
29
-Se
p-1
5
6-O
ct-1
5
13
-Oct
-15
20
-Oct
-15
Tem
pe
ratu
re °
C
Date
Lobster Bay Lobster Collector Temperatures 2015
Lears Island
Goosberry Island
Abbotts Harbour
French Point
Canoe Island
Johns Island
Lobster Island
0123456789
1011121314151617181920
5-A
ug-
15
12
-Au
g-1
5
19
-Au
g-1
5
26
-Au
g-1
5
2-S
ep
-15
9-S
ep
-15
16
-Se
p-1
5
23
-Se
p-1
5
30
-Se
p-1
5
7-O
ct-1
5
14
-Oct
-15
21
-Oct
-15
28
-Oct
-15
4-N
ov-
15
Tem
pe
ratu
re °
C
Date
False Bay Lobster Collector Bottom Temperatures 2015
Shallow
Deep
0123456789
10111213141516171819
15
-Ju
n-1
5
22
-Ju
n-1
5
29
-Ju
n-1
5
6-J
ul-
15
13
-Ju
l-1
5
20
-Ju
l-1
5
27
-Ju
l-1
5
3-A
ug-
15
10
-Au
g-1
5
17
-Au
g-1
5
24
-Au
g-1
5
31
-Au
g-1
5
7-S
ep
-15
14
-Se
p-1
5
21
-Se
p-1
5
28
-Se
p-1
5
5-O
ct-1
5
Tem
pe
ratu
re °
C
Date
St. Mary's Bay Lobster Collector Temperatures 2015
Cherry Valley
Skinny Shoal
Long Beach
Big Shoal
0123456789
1011121314151617181920
6-J
ul-
15
13
-Ju
l-1
5
20
-Ju
l-1
5
27
-Ju
l-1
5
3-A
ug-
15
10
-Au
g-1
5
17
-Au
g-1
5
24
-Au
g-1
5
31
-Au
g-1
5
7-S
ep
-15
14
-Se
p-1
5
21
-Se
p-1
5
28
-Se
p-1
5
5-O
ct-1
5
12
-Oct
-15
19
-Oct
-15
26
-Oct
-15
Tem
pe
ratu
re °
C
Date
Whitehead Lobster Collector Temperatures 2015
