A Review of Ghost Gear Entanglement Amongst Marine Mammals, Reptiles and Elasmobranchs
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See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/304455158 A review of ghost gear entanglement amongst marine mammals, reptiles and elasmobranchs Article in Marine Pollution Bulletin · June 2016 DOI: 10.1016/j.marpolbul.2016.06.034 CITATIONS READS 6 693 3 authors, including: Jillian Hudgins Michael John Sweet Olive Ridley Project University of Derby 15 PUBLICATIONS 68 CITATIONS 75 PUBLICATIONS 726 CITATIONS SEE PROFILE SEE PROFILE Some of the authors of this publication are also working on these related projects: CORALASSIST: Assisting Coral Reef Survival in the Face of Climate Change View project Coral Disease Research in Indonesia View project All content following this page was uploaded by Michael John Sweet on 05 July 2016. The user has requested enhancement of the downloaded file. MPB-07798; No of Pages 12 Marine Pollution Bulletin xxx (2016) xxx–xxx Contents lists available at ScienceDirect Marine Pollution Bulletin journal homepage: www.elsevier.com/locate/marpolbul Review A review of ghost gear entanglement amongst marine mammals, reptiles and elasmobranchs Martin Stelfox a,b,⁎, Jillian Hudgins b, Michael Sweet a a Environment Sustainability Research Centre, College of Life and Natural Sciences, University of Derby, UK b Olive Ridley Project, 8 Thornton Avenue, Plymouth, UK article info abstract Article history: This review focuses on the effect that ghost gear entanglement has on marine megafauna, namely mammals, rep- Received 25 April 2016 tiles and elasmobranchs. A total of 76 publications and other sources of grey literature were assessed, and these Received in revised form 6 June 2016 highlighted that over 5400 individuals from 40 different species were recorded as entangled in, or associated Accepted 8 June 2016 with, ghost gear. Interestingly, there appeared to be a deficit of research in the Indian, Southern, and Arctic Available online xxxx Oceans; and so, we recommend that future studies focus efforts on these areas. Furthermore, studies assessing Keywords: the effects of ghost gear on elasmobranchs, manatees, and dugongs should also be prioritised, as these groups Ghost net were underrepresented in the current literature. The development of regional databases, capable of recording en- Ghost fishing tanglement incidences following a minimum global set of criteria, would be a logical next step in order to analyse Ghost gear the effect that ghost gear has on megafauna populations worldwide. Entanglement Crown Copyright © 2016 Published by Elsevier Ltd. All rights reserved. Derelict gear Megafauna Contents 1. Introduction............................................................... 0 1.1. Supply and demand - A brief look at global fishingpressure...................................... 0 1.2. When does fishinggearbecomeALDFG?............................................... 0 1.3. What factors affect ghost fishingrates?................................................ 0 1.4. The cyclical nature of ghost fishingandtheroleofbio-fouling..................................... 0 2. Materialsandmethods.......................................................... 0 3. Results................................................................. 0 3.1. The effects of ghost fishingonmarinemammals,reptilesandelasmobranchs.............................. 0 3.2. Geartype............................................................. 0 3.3. Biasinresults........................................................... 0 4. Discussion................................................................ 0 4.1. Cetaceans and ghost fishing..................................................... 0 4.2. Pinnipeds and ghost fishing..................................................... 0 4.3. Manatee and dugong and ghost fishing................................................ 0 4.4. Marine turtles and ghost fishing................................................... 0 4.5. Elasmobranchs and ghost fishing.................................................. 0 4.6. Managementandmitigation.................................................... 0 5. Conclusions............................................................... 0 References.................................................................. 0 1. Introduction fi fi ⁎ Corresponding author at: Environment Sustainability Research Centre, College of Life Though shing gear has been lost since shing began, historically and Natural Sciences, University of Derby, UK. such gear was made from natural materials that would have http://dx.doi.org/10.1016/j.marpolbul.2016.06.034 0025-326X/Crown Copyright © 2016 Published by Elsevier Ltd. All rights reserved. Please cite this article as: Stelfox, M., et al., A review of ghost gear entanglement amongst marine mammals, reptiles and elasmobranchs, Marine Pollution Bulletin (2016), http://dx.doi.org/10.1016/j.marpolbul.2016.06.034 2 M. Stelfox et al. / Marine Pollution Bulletin xxx (2016) xxx–xxx decomposed quickly and created a relatively small threat to marine steel that would corrode quickly (Campbell & Sumpton, 2009). This wildlife. However, in recent years advances in technology and improve- change in gear design was most likely driven by the cost of the new ments in gear designs have forced fishers to switch to gear made from nets and pots, as they are cheaper to purchase and, they are easy to re- synthetic materials, namely plastics (e.g., Macfadyen et al., 2009). Syn- place if, or when, they are damaged. thetic fishing materials such as nylon, polyethylene, and polypropylene are impervious to natural biodegradation and can remain unchanged in 1.2. When does fishing gear become ALDFG? the marine environment for decades. This promotes a phenomenon called ‘ghost fishing’, whereby lost or discarded gear continue to catch Fishing gear becomes ALDFG when the fisher loses all operational an abundance of wildlife from a range of taxa. The actual amount of control of the equipment (Smolowitz, 1978). A switch from the natural abandoned, lost, or otherwise discarded fishing gear (often shortened or biodegradable material that was traditionally used for centuries to to ALDFG) is extremely difficult to quantify. However, it has been esti- synthetic fishing gear (as described above) has led to a rise in the mated that each year, upwards of 640,000 tons of gear is lost globally, amount of ALDFG accumulating in the world's oceans. The causes of meaning that ALDFG accounts for over 10% of the total marine debris ALDFG include: snagging on the bottom, storms or bad weather, opera- floating in our oceans (Macfadyen et al., 2009). Given that survey effort tional damages, improper gear use, gear conflicts, high cost relating to for ALDFG is often poor or sporadic in many areas around the world, this proper disposal, lack of disposal facilities, lack of space on fishing craft, 10% is therefore likely to be a gross underestimate of the true amount. and logistical difficulties retrieving gear. For a summary of the multitude As early as the 1980s, the Food and Agriculture Organisation (FAO) of reasons why fishing gear may be lost we refer you to Macfadyen et al. recognised ALDFG as a global problem. ALDFG also fits under the man- (2009). date of the International Maritime Organisation (IMO), which heads the International Convention for the Prevention of Pollution from 1.3. What factors affect ghost fishing rates? Ships (MARPOL Annex V). Furthermore, the issue has been raised at nu- merous United Nation general assemblies (Macfadyen et al., 2009). Al- Ghost fishing is defined as the ability of fishing gear to continue to though ALDFG is clearly a global concern affecting many species, it is fish after all control of that gear is lost (Smolowitz, 1978). This definition important to pay particular attention to those species that are sensitive however, does not give specifics on how to identify mortality rates asso- to anthropogenic stress (i.e., those with low fecundity or increased age ciated with ghost fishing. Matsuoka et al. (2005) suggested that the at sexual maturity). presence of lost fishing gear and the entry of organisms into that gear, This review focusses on how entanglement in ALDFG impacts ma- for example, was not substantial enough evidence to prove that the rine megafauna, such as mammals, reptiles and elasmobranchs. Num- gear was ‘ghost fishing’. Additionally, the identification of any dead an- bers were pulled from all traceable literature dating back to the last imals must be conducted to species level in order to give reliable mortal- comprehensive review conducted by Laist (1997). We also aimed to ity rates of ghost fishing. The survival rate of animals that have escaped identify the different gear types that contribute to ghost fishing and entanglement must also be considered; a problem that is more difficult give recommendations on how to manage and mitigate the issue. to quantify. Using a terrestrial example of entanglement and mortality, a study by Votier et al. (2011) argued that colonial seabirds released from 1.1. Supply and demand - A brief look at global fishing pressure entangling plastic would not survive without human intervention. They suggested that individuals that had escaped or were released from the Fishing pressure has increased dramatically worldwide since the gear would likely succumb to death as a direct result of the entangle- 1970s (Anticamara et al., 2011). It is thought that a growing global ment and should, therefore, also be considered in the mortality human population, combined with higher incomes and an insatiable ap- estimate.