The Science of Marine Conservation: what we know, what we don't know (yet) and what we'll never know

1. The Science of Marine Conservation: what we know, what we don't know (yet) and what we'll never know (Presentation to the Endeavour Society at Bangor University on 27th November 2008) Keith Hiscock

2. Main topics in the presentation • Knowing what’s out there (biodiversity-wise) • Knowing how to organize biodiversity information • Knowing how marine ecosystems ‘work’ • Knowing about and understanding change – natural and anthropogenic • Knowing about recovery potential • Explaining and predicting change – what we think we (might) know • What we don’t know – what’s around the corner? For further reading, see reference lists in reports accessible on www.marlin.ac.uk/pap and www.ukmpas.org

3. We know that we have some fabulous marine life in UK waters Plymouth Drop-off, 30m

4. Yes, even in locations like this Heybridge Basin, Blackwater Estuary

5. Not forgetting, the charismatic megafauna

6. We know how to organize information – classification of species and numbers 35 major groups of organisms in the sea, 15 on land 8, 229 multicellular marine species listed in the Species Directory for Britain and Ireland See:www.marlin.ac.uk/PDF/MLTN_biodiversity.pdf Taxonomic tree from www.coastal.edu

7. We know how to organize information - marine habitats (biotopes) 262/370 biotopes (at Level 4/5) in the 2004 classification (Connor et al. 2004. See: www.jncc.gov.uk/page-1584) Phymatolithon calcareum maerl beds with hydroids and echinoderms in deeper infralittoral clean gravel or coarse sand (Code: IGS.Phy.HEc). Image: Keith Hiscock

8. And, we can classify them: The EUNIS biotopes classification

9. We know about the distribution of species - much as they were 150 years ago Forbes, E. (1858). The Distribution of Marine Life, illustrated chiefly by Fishes & Molluscs & Radiata. In A.K. Johnston's Physical Atlas, pp. 99-101, Edinburgh

10. We know how marine ecosystems ‘work’: – the major physical, chemical and biological factors that ‘drive’ marine systems (essential to know for the ‘ecosystem approach’): From Hiscock et al. 2006. The structure and functioning of marine ecosystems: an environmental protection and management perspective. MarLIN report to English Nature. (Drawing: Keith Hiscock & Jack Sewell). Access from: www.marlin.ac.uk/pap.

11. And, what are the inputs and outputs Some physical, chemical and biological factors affecting a small marine habitat

12. Mean dispersal distance estimates for marine benthic organisms. From: Kinlan, B. P., and S. D. Gaines. 2003. Propagule dispersal in marine and terrestrial environments: a community perspective. Ecology 84: 2007-2020. We know - that many marine species have poor dispersal potential (important for understanding connectivity and networks):

13. Hunstanton beach after a storm We know - that ecosystems change, naturally

14. The rocky subtidal communities at Hilsea Point Rock are very similar to those described over 50 years ago (Hiscock, 2005, JMBA 85, 1009-1010) We know that some habitats and associated species are similar to historical descriptions

15. We understand that small scale disturbance will be unlikely to change the biotope present and recovery is possible even from large scale disturbance • but it may be difficult or impossible to facilitate reversal of effects of abnormal or very large scale disturbance We know: that disturbance can change ecosystems – sometimes ‘for ever’

16. Extraction (aggregates) : • substratum loss; • smothering by sediment plume; • loss of substratum stability. From Kenny & Rees, 1994. MPB 28, 442-447 We know that recovery can occur from human activities See: Boyd, et al. 2004. Assessment of the rehabilitation of the seabed following marine aggregate dredging. CEFAS Technical report No. 121.

17. Including through the establishment of Highly Protected Marine Reserves Leigh, New Zealand: ‘Urchin barrens’ like this in 1976

18. But with protection predators not only become commoner, they also grow larger Image: Bill Ballantine

19. Large rock lobster can open large sea urchins

20. so now, kelp forest or turf See: Langlois, T.J. and Ballantine W.J. 2005. Marine ecological research in New Zealand: developing predictive models using no-take marine reserves. Conservation Biology 19:1763-1770. Image: Tony Ayling

21. The highly protected area at Lundy: increasing lobster stocks

22. Abundancesof lobsters • ANOVA tests: • Year x NTZ vs Control: • Non significant • (F3,3 = 0.19, P = 0.89) • Year x NTZ vs Reference: • Non significant • (F3,3= 5.25, P = 0.10) Near Far

23. Haddock CPUE Lbs./hour fishing Closed Area I 0 lbs. 0.1-500 lbs. 501-1000 lbs 1001-3000 lbs. 3001-7500 lbs/hr Areas closed to fishing can be beneficial to fisheries - spillout Murawski, S. A., S. E. Wigley, M. J. Fogarty, P. J. Rago, and D. G. Mountain. 2005. Effort distribution and catch patterns adjacent to temperate MPAs. ICES Journal of Marine Science62:1150-1167.

24. 7 For a summary of benefits of marine reserves: Partnership for Interdisciplinary Studies of Coastal Oceans. 2007. The Science of Marine Reserves (2nd Edition, International Version). www.piscoweb.org/outreach/pubs/reserves

25. Some of what we know about impacts is obvious and does not need hypothesis driven, statistically robust, expensive, delaying, and distracting research Lyme Bay reefs: Devon Biodiversity Records Centre

26. Knowing about recovery potential - some species are unlikely to return if they are lost Axinella dissimilis: growth rate <1mm a year Species that are slow growing, have short-lived larvae and reproduce infrequently are unlikely to recover - ever

27. Non-native species have changed natural habitats and assemblages forever. Construction has built on or removed natural habitats forever. Some ‘for ever’ changes are obvious:

28. Some species and biotopes we should protect now, identified by ‘Threat of significant decline’ criteria* Fragile species with short-lived propagules and/or that are long-lived, slow growing and may recruit infrequently (including that are key biotopes components). For instance: Sunset coral. Larva short-lived, settles very near parent. Deep sponge biotope. Very slow-growing & long-lived component species ? (No colonisation of new surfaces). Fan mussel, Atrina fragilis. Very long-lived larva. Devastated by mobile fishing gear. * Defra, 2005. Review of Marine Conservation – Working Group report to Government. PB 9714. London, Department for Environment, Food and Rural Affairs. http://www.defra.gov.uk/wildlife-countryside/ewd/rmnc/pdf/rmnc-report-0704.pdf

29. Including ‘recovery potential’ in assessing ‘sensitivity’ Sensitivity is identified from the intolerance of a species or habitat to damage from an external factor and the time taken for its subsequent recovery. www.marlin.ac.uk

30. We know that climate change (especially warming) is happening 13.5 13.5 13.0 13.0 12.5 12.5 Mean annual SST (ºC) Mean annual SST (ºC) 12.0 12.0 11.5 11.5 11.0 11.0 1905 1905 1925 1925 1945 1945 1965 1965 1985 1985 2005 2005 Year Year Data source: Met Office Hadley Centre Grid square 50-51ºN, 4-5ºW See also Sheppard, 2004, Mar. Poll. Bull., 49: 12-16

31. In the UK: southern species – advancers? Laminaria ochroleuca Paracentrotus lividus Eunicella verrucosa Anemonia viridis In the UK: northern species – retreaters? Strongylocentrotus droebachiensis Bolocera tuediae Alaria esculenta Swiftia pallida Which species will be winners or losers? See Hiscock et al. 2004. Aquatic Conservation 14, 333-362.

32. Unraveling interactions - fish populations have changed in abundance, size and species composition – climate or fishing? October 1963 November 2001 The MBA has maintained long-term data sets on fish populations since 1911. Sharpest declines seen in large species: skate & ray, brills, conger eel

33. We think we know which species are being affected by warming v. fishing Species correlated with more fishing (No cold water species losses correlated with warming) Species increasing with warming Species declining with fishing Genner, Sims, Southward, & Hawkins, 2004, Proc. Roy. Soc., 271, 655-661.

34. We do not know ‘what is where’ www.searchmesh.net

35. And seabed maps are often wrong (The seabed west of Rame Head is predominantly rock, not fine sand)

36. Lundy Knoll Pins 2001 Lundy Knoll Pins 1986 We do not know why some changes (e.g. at Lundy) are occurring

37. But we can make some informed guesses Natural cycles or events? Seawater fertility:“… the difference in bottom fauna from one region to another may be related to the ability, or otherwise, of larval stages to develop in the overlying water mass. (Wilson, 1951. JMBA 30, 1-19) Seawater type: “ ….. the numbers of postlarval fish and of other species especially decapods were very abundant in the plankton off Plymouth in the 1920's, declined in the 1930's, and stayed low until somewhere around 1965 when a marked increase in the macroplankton, including fish larvae occurred. Abundance is high when water masses off Plymouth become of the ‘Sagitta elegans’ type. (Russell, 1973. JMBA 53, 347-355). Alan Southward, in the Cooper Memorial Lecture on 31 March 1998, suggested that what is now known as the ‘Russell Cycle’ returned to its 1920's peak between 1965 and 1979. The North Atlantic Oscillation may also be important. Disease? Disease:certainly the case for conspicuous mortality in sea fans (Vibrio splendidans – or something like it -did it), but was anything else affected? And, is likelihood of disease exacerbated by high nutrient levels? Contamination via human activities? Elevated nutrients (perhaps working with warming events): Environment Agency (1999) in the State of the Environment’ report notes that nutrient levels in the Bristol Channel are elevated. Contaminants: in the case of severe contamination (for instance by TBT), species richness in enclosed areas can be halved (Rees et al. 2001. Mar. Poll. Bull. 42, 137-144.) Toxic phytoplankton? The non-native dinoflagellate alga Karenia mikimotoi (previously Gymnodinium aureolum) is now very widespread and is known to be responsible for mass mortalities of benthic species – does it have a sublethal or low-level mortality effect that may reduce resistance and vigour?

38. Fish and invertebrates killed by a bloom of the non-native dinoflagellate alga Karenia mikimotoi (previously Gymnodinium aureolum) in Killary Harbour in July 2005. Image: Rohan Holt. A red tide What we don’t know – what’s around the corner? Another non-native species – probably the next nasty surprise

39. Functioning. The mode of action by which the system fulfils its purpose or role, as determined by its component elements. In terms of ecosystem functioning; the activities, processes or properties of ecosystems that are influenced by its biota (Naeem et al., 2004). Naeem, S., Loreau, M., & Inchausti, P., 2004. Biodiversity and ecosystem functioning: the emergence of a synthetic ecological framework. In: Biodiversity and Ecosystem Functioning (ed. S. Loreau, S. Naeem & P. Inchausti), pp. 3-11. Oxford: Oxford University Press. What we don’t know – importance of biodiversity for ecosystem functioning (and the supply of goods and services) Research requirements identified via the UK Biodiversity Research Action Group (BRAG) at the initiative of Defra and the Joint Nature Conservation Committee (report awaited) – but a whole separate lecture!

40. What we’ll never know Enough! • to predict, with precision, the consequences of human activities on marine habitats and species and the likely prospects for recovery to what extent; • to understand the role of all of the species in a habitat for ecosystem functioning; • to anticipate the character and scale of natural fluctuations; • to separate with absolute certainty the effects of human activities from natural change. So, the easy questions are answered, and the difficult ones are left for you to solve.

41. you and your children will still be able to see this www.mba.ac.uk We still have lots of fabulous marine life and, with political action, good will and good luck,