Estimating the minimum size for inshore notake marine

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Estimating the minimum size for inshore no-take marine protected areas in the i. Simangaliso

Estimating the minimum size for inshore no-take marine protected areas in the i. Simangaliso Wetland Park based on movement patterns of surf-zone fish species Bruce Mann 1 and Paul Cowley 2 1. Oceanographic Research Institute 2. South African Institute for Aquatic Biodiversity

Fish are more abundant in NTAs than elsewhere (Catch per 100 angler-hours) Areas with

Fish are more abundant in NTAs than elsewhere (Catch per 100 angler-hours) Areas with fishing Areas without fishing Attwood and Bennett (1995) South African Journal of Marine Science 16: 227 -240.

Fish are much larger in NTAs than outside Areas with fishing Areas without fishing

Fish are much larger in NTAs than outside Areas with fishing Areas without fishing Maggs et al. (2013) Fisheries Research 144: 38 -47

Big Old Fat Fecund Female Fish (BOFFFF Hypothesis) • Lay way more eggs •

Big Old Fat Fecund Female Fish (BOFFFF Hypothesis) • Lay way more eggs • Lay larger eggs with better survival rates • Offspring genetically fitter Berkeley et al. (2004) Ecology 85(5): 1258 -1264

Spillover and seeding into adjacent fished areas Kerwath et al. (2013) Nature Communications 4(2347):

Spillover and seeding into adjacent fished areas Kerwath et al. (2013) Nature Communications 4(2347): 1 -6

“Where movement patterns of fishery species are known, this information can be used to

“Where movement patterns of fishery species are known, this information can be used to inform decisions taken about the configuration of no-take areas to maximize benefits for biodiversity conservation, fisheries management and improving resilience against climate change” Green et al. (2014) Coastal Management 42(2): 143 -159

Aims of project • To determine movement patterns of shore angling fish species in

Aims of project • To determine movement patterns of shore angling fish species in the St Lucia Marine Reserve on a fine spatial scale using tag-recapture methodology • To estimate the home range sizes of these species • To determine the minimum size that no-take areas need to be to protect populations of these species • To determine the distance apart such no-take areas need to be in order to ensure connectivity between protected fish populations • To improve the current network of inshore no-take areas within the i. Simangaliso Wetland Park to optimize biodiversity protection and fishery management goals

METHODS • • • Started November 2001 4 trips per year 8 trained anglers

METHODS • • • Started November 2001 4 trips per year 8 trained anglers per trip Two 4 x 4 vehicles Comparison between 4 areas

Use of standardized fishing gear and barbless hooks

Use of standardized fishing gear and barbless hooks

Landing of fish in specially made plastic stretchers

Landing of fish in specially made plastic stretchers

Careful fish handling, measuring and tagging (> 30 cm FL)

Careful fish handling, measuring and tagging (> 30 cm FL)

Quick release using the stretcher

Quick release using the stretcher

A recaptured speckled snapper

A recaptured speckled snapper

RESULTS • 15 325 fish caught and released during 59 field trips (Nov 2001

RESULTS • 15 325 fish caught and released during 59 field trips (Nov 2001 to Nov 2013) • 6 613 fish tagged (71 species) and 1 004 (15. 2%) fish recaptured (17 species)

Explanation of home range and NTA size • Home range size was quantified for

Explanation of home range and NTA size • Home range size was quantified for each species by taking the 95 th percentile of intra-study site movement distances only, and excluded all long-distance movements (> 2 km) where fish abandoned their home range and did not return. • NTA size was estimated by doubling the home range size in all directions (i. e. multiplying by three for a linear habitat such as the surf-zone)

Species No. tagged No. recaptured Home range length (km) Ranging movement (km) Minimum NTA

Species No. tagged No. recaptured Home range length (km) Ranging movement (km) Minimum NTA length (km) Giant sandshark 55 5 (9. 1%) 1. 8 (n=3) 5. 2 (n=2) 5. 4 Catface rockcod 325 57 (17. 5%) 0. 5 (n=56) 34. 3 (n=1) 1. 5 Yellowbelly rockcod 295 73 (24. 8%) 0. 7 (n=70) 2. 7 -6. 8 (n=3) 2. 1 Potato bass 236 11 (4. 7%) 0. 7 (n=11) None 2. 1 Lemon fish 158 10 (6. 3%) 0. 3 (n=10) None 0. 9 White-barred rubberlip 46 1 (2. 2%) 0. 1 (n=1) None 0. 3 Grey grunter 817 57 (7. 0%) 0. 7 (n=57) None 2. 1 Cave bass 479 96 (20. 0%) 0. 5 (n=91) 3. 5 -90 (n=5) 1. 5 River snapper 20 2 (10. 0%) 0 (n=2) None - Speckled snapper 1308 652 (49. 9%) 1. 0 (n=614) 2. 1 -125 (n=38) 3. 0 Zebra 16 1 (6. 3%) 0 (n=1) None - Natal stumpnose 529 16 (3. 0%) 1. 9 (n=14) 9. 4 -230 (n=2) 5. 7 Dusky kob 29 2 (6. 9%) - 14 -17 (n=2) - Bluefin kingfish 30 3 (10. 0%) 0. 9 (n=3) None 2. 7 Blacktip kingfish 141 5 (3. 6%) 0. 6 (n=2) 3 -26 (n=3) 1. 8 Smallspot pompano 1 1 (100%) 0. 2 (n=1) None 0. 6 Largespot pompano 1327 12 (0. 9%) 1. 2 (n=9) 6. 6 -114 (n=3) 3. 6

How far apart should NTAs be spaced? • Based on best available estimates of

How far apart should NTAs be spaced? • Based on best available estimates of larval fish dispersal in the literature, Green et al. (2014) recommended a maximum distance of 15 km between NTAs to ensure sufficient connectivity. • Average distance moved by ranging individuals in this study (i. e. those that abandoned their home range) was 17 km. • Therefore the recommendation to protect resident surf-zone fish species was NTAs of 3 -6 km in length consisting of suitable reef habitat spaced every 1520 km apart.

Recommendations • Existing NTAs need to be clearly demarcated (i. e. signposted) and their

Recommendations • Existing NTAs need to be clearly demarcated (i. e. signposted) and their position and purpose needs to be effectively communicated to both recreational anglers and subsistence shore fishers and intertidal invertebrate harvesters. • Demonstration projects should be established to convince resource users of the need for NTAs and ultimately to obtain their support and compliance. • Within existing NTAs efforts should be made with the affected communities to decide on a minimum of 3 km of the best available habitat where they will agree to stop fishing and harvesting.

Recommendations continued • Identified gaps in the network of NTAs along the shore (i.

Recommendations continued • Identified gaps in the network of NTAs along the shore (i. e. Lala Nek and Nine-mile) should be implemented in consultation with local communities, recreational fishing associations and the general public. • Once agreed to by relevant user groups, compliance with NTAs needs to be effectively enforced by the conservation authority (Ezemvelo). • Effective monitoring of both recreational shore angling catch and effort and subsistence use of marine living resources needs to be continued, as should research monitoring within the NTAs

CONCLUSION • Simple, practical science involving anglers and other stakeholders can be used to

CONCLUSION • Simple, practical science involving anglers and other stakeholders can be used to improve effective conservation • The current proposal will ensure protection of 30% of the coastline within the i. Simangaliso Wetland Park in no-take areas which is supported by recent recommendations from the World Parks Congress (Nov 2014) • Our Mother Ocean (OMO) knows how to look after herself – we simply need to give her a chance by protecting a suitable network of representative no-take areas • Please help to support the establishment and management of MPAs and ensure that our existing no-take areas are kept sacrosanct!

Acknowledgements • 101 anglers that have voluntarily contributed their time to this project over

Acknowledgements • 101 anglers that have voluntarily contributed their time to this project over the past 12 years • SAAMBR, the previous Department of Environmental Affairs and Tourism and the i. Simangaliso Wetland Park Authority for funding • Ezemvelo KZN Wildlife for logistic support Thank you for your attention!