Fish as Biomarkers

How would you determine the effects of an oil spill on a marine environment? Most responses would be to test the level of contaminants in the water. While this test would give the levels how does it relate to the health of the biotic marine life forms? Simply carrying out physical and chemical tests of the abiotic environment is not comprehensive enough to represent the health of the entire marine environment. Coupling these methods with the use of biomarkers is a more comprehensive approach. A biomarker is the biological measure of an organism’s biological state this was a definition given by a doctor (Mandal 2016).

Picture taken from Intech Open

When choosing an organisms or species as a biomarker in oil spill it must be representative of the ecosystem affected. Fishes have both molecular and cellular defense systems to protect them from harmful substances. This includes detoxifying enzymes and molecules which are used to determine the impact of oil on the organism as well as its environment (Sturve, 2014). To get on how the marine ecosystem is progressing in the wake of the oil spill constant testing or monitoring is done on fishes at the location. Also knowing the extent to which the adult fishes were impacted can give an early indication on how future offspring in turn would be impacted. Use of biomarkers or biomonitoring can be done for years to give an idea of how the marine environment is coping long after the spill. In most cases the values given by biomarkers decrease over time indicating that the environment it returning to normalcy.

References

Ananya Mandal 2016. What is a Biomarker, News Medical Life Sciences Retrieved from http://www.news-medical.net/health/What-is-a-Biomarker.aspx

Joachim Sturve, Lennart Balk, Birgitta liewenborg margaretha Adolfsson-Erici, Lars Forlin and Bethanie and Carney Almroth 2014 Effects of an oil spill in a harbor assessed using biomarkers of exposure in eelpout Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4236613/

Fish, Artificial Habitat, Oil Platform (Rigs to Reefs)

On most occasions when we hear about oil and fish together we think of some disaster in which fishes are killed in large numbers and a bunch of associated ecosystem impacts. Though this trend of thought does hold some truth it is not always so. Thanks to oil platforms erected in the oceans there is as at least one positive relation between oil and fish. The structures are favourable for fishes and other organisms such that it acts as an artificial habitat. The lattices of the platforms have a large surface area this is the type of habitat demersal fish such as Rockfish seek. It provides them with shelter, food and a place to hide and avoid predators (Goldfarb, 2014). Normally after oil activities have ceased these platforms are decommissioned (Love et.al. 2015). This means that the platform is removed; however the “Rigs to Reefs” concept considers the fish habitat present. As a result the entire platform is not removed and the fish get to keep their habitat. In some cases such as in Louisiana liability of the rig is transferred from the operator to the state this was reported by (The Environmental News Network, 2013).

Picture by the Gulf of Mexico Foundation

The larger surface area of the platform does not benefit just Rockfish but other fish as well. It provides them with the same protection from predators. The surface area ratio provided by the platform compared to that of the rocky seafloor can be more suitable for fish. As a result the secondary production there is greater than that of natural ecosystems. Secondary production is the sum of new biomass from individual organisms in an area over a particular time period. This suggests that organisms, fish in particular thrive better in the artificial habitat at the platform. Also studies have shown that outside organisms also move to the platform to live, they are said to be recruited. Another interesting fact is that there are assemblages of fish at different heights of the platform (Claisse et. al, 2014). The younger fish tend to be at the higher levels and move to lower levels as adults. Sometimes adult fish leave the platform altogether to live in other environments. However a true statement would be to say that without the platform many fish species would not have survived in the open ocean. This could be because of the food web that is developed at these platforms as there are so many organisms present. Plankton is one food source fed on by small fish and these fish provide food for larger fishes there. So predation is not absent in this habitat just greatly reduced.

Picture taken from Flower Garden Banks, National Marine Sanctuary 

Some fish species at the platform are commercial fish and as a result fishing activity there does contribute to the economy. However there is a concern about the exploitation of fish there. This is as a result of the biomass and population there developing so quickly that it gives the impression that the population is resilient enough to support constant fishing. Another unsettling factor is the possibility of seepage from the capped platform. This could lead to contamination of fish at the platform. In a study done on a capped platform, it was found that the fish there, had similar amounts of polycyclic aromatic hydrocarbons (contaminant) when compared to fish away from the site. Therefore this would suggest that contamination risk is low for a well capped rig.

Personally I believe the rig to reef concept is a great idea and would hope to actually witness one in the near future.

References

Ben Goldfarb, 2014, Offshore Oil Rigs can provide prime fish habitat, High Country News Retrieved from http://www.hcn.org/articles/offshore-oil-rigs-can-provide-prime-fish-habitat

The Environmental News Network, 2013. Oil Platform’s Effects on Fish Populations, OilPrice.com Retrieved from http://oilprice.com/Energy/Energy-General/Oil-Platforms-Effect-on-Fish-Populations.html

JeremyT Claisse, Danile J. Pondella II, Laurel A. Zahn, Chelsea M. William, Johnathan P. Williams and Ann S. Bull, Oil platform off California are among the most productive marine fish habitats globally, Retrieved from  www.pnas.org/content/111/43/15462

OIL PRESENCE IN FISHERIES

When one thinks of an oil spill in the ocean they rarely consider that it could affect fisheries, as they are controlled environments. Despite this fact, efforts still have to be made to protect it. In fact these areas may need more protection as there is valuable equipment housed there. Unlike the open ocean where fishes can swim away from oil this is not so for fishes in fisheries. They are usually in a restricted space so escape is not really an option. Fish there are also subject to taint as well as polycyclic aromatic hydrocarbons as fish in the ocean. This means they also buildup build up toxic substances in their tissue, experience reproductive problems, mutations and heart defects. However the fish are easy to monitor as they are at a particular location. Therefore the contaminated fish can be given time for the contaminants to naturally be removed from their tissues (ITOPF, 2004). This process is called depuration. Fish are constantly monitored for contaminant concentrations and when an acceptable level is reached they can then be used commercially. The limitation of this depuration time period is that the fish may grow larger than the required size for sale. Apart from commercial use there are fisheries for recreation that also support the economy for example there is the presence of bait and tackle shops there as well as other businesses (Upton, 2011).

                                   

fig 1 taken from http://spacecollective.org/matthewspencer

fig 2 taken from http://www.constantinealexander.net/science/page/69/

The pictures show how fish is reared in a controlled environment. The fish here depend on their fish farmers to supply food as opposed to hunting for themselves. Also they are safe from predators so overall this environment provides very few stressors. However it is easy to see how floating oil can enter these areas as they appear very unguarded. Fig 1 shows an Aquapod which has an innovative design and is suited for rough conditions as it is dynamic due to suspension cables and not being attached to other pods. Fig 2 show fish rearing cages arranged close to each but with enough space for small boats to pass through. This access allows for feeding to be done more efficiently.   

It is difficult to know how much an oil spill has affected a fishery as other external factors come in to play. Some include climate, natural population decline and increased fishing. Also conditions at the fishery before an oil spill may be unknown so its impact is not certain. Therefore changes in fish populations can result from a single or a variety of reasons. One of the greatest impacts known to be caused by oil was experienced by fisheries in Louisiana. Fisheries there supply 40% of the U.S. seafood supply. The effects of the Gulf of Mexico oil damaged fisheries to the extent that reporters (Matthew Biggin Venice et. al, 2010) of Reuters described it as a “Fishery Disaster”.

There is various equipment utilized at fisheries, these include lift nets, buoys, cast nets and fixed traps. All this surface equipment is susceptible to floating oil and as a result can become contaminated. Subsurface equipment can become contaminated if it is lifted through the surface coming in contact with oil there. Contaminated equipment can contaminate fish; therefore it must be cleaned, in some cases it must be dismantled before cleaning. The cleaning process involves the use of a pressure washer to remove oil. If the cost to clean exceeds the cost of new equipment the latter option is chosen. Booms and barriers are used to protect fish gear by containing floating oil preventing its spreading. It works well in calm waters but is not effective in more harsh conditions as waves may carry oil over the boom (Tech- Faq). On the other hand a protection method for the fish is the placing of heavy plastic sheets around their cages and securing it at the base. This is so that currents cannot cause the plastic to be removed exposing fish in the cage to oil. Fish tanks on shore as the name implies supports fish. The tank is linked to the sea via a pipeline and in cases where dispersed oil is in the water column the line is closed. This dispersed oil can be carried into the fish tank contaminating the pipeline on the way. This could result in the loss of the entire fish stock housed. 

Overall fisheries are very important to economies throughout the world so it is important to protect it. We as citizens can do our part by limiting the amount of oil derived substance carried to the ocean as run off. It is important to remember that the ocean is where all waterways ultimately lead to.



References

Harold F. Upton. The Deepwater Horizon Oil Spill and The Gulf of mexico Fishing Industry Retrieved from https://www.fas.org/sgp/crs/misc/R41640.pdf

Matthew Biggin Venice, SteveGorman and Pascal Fletcher. Factbox: Gulf Oil Spill impacts, fisheries, wildlife, tourism, Reuters Retrieved from http://www.reuters.com/article/us-oil-rig-impact-factbox-idUSTRE64T23R20100530

Tech-Faq. How Do Booms Work? Retrieved from  http://www.tech-faq.com/how-do-oil-booms-work.html

ITOPF 2004. Effects of Oil Pollution on Fisheries and Mariculture, Retrieved from  https://www.scribd.com/document/191508407/Itopf-Oil-Spill-Effects-on-Fisheries

Ways to Control Oils Spills from Tankers: A Proactive Approach

When an oil spill occurs in the ocean, some of the major concerns involve the extent of ecological damage, cleanup methods and cost. What if it was possible to stop the spill from ever occuring? In previous blogs I looked at  the effects oil spills had on the fish population. However in this blog I shed light on some approaches used to limit oil spills from oil tankers to protect fish. 

Many would agree that a price cannot be placed on ecological loss, as its recovery after a spill takes many years. For this reason the transport of oil across the ocean is a risky task. To conduct activities on tankers that facilitate this transport, a capable staff must be available. Capable or not there are laws against the release of oil and to ensure compliance with these laws there are policies that contain monitoring and penalties that seek to help reduce oil spills. In regard to the laws the Coast guard and the Environmental Protection Agency are example of those that have the power to enforce them (Cohen, 2009).

Everybody knows the difference between right and wrong or so I would like to believe. There is a saying that “one does the correct thing when supervised”. I believe this is the main reason for monitoring of oil vessels. It is said that a crew working on an oil vessel, does so with more integrity when they know they are being watched. To avoid consequences such as penalties mentioned earlier, they comply with the law. Beside skill the morals of the crew must also be questioned as some oil spills are deliberate. This is done to save expenses on proper methods of cleaning ships. A report by (Parker, 2016) indicated that two engineers on an Italian oil tanker received felony charges for the dumping of oil into the ocean. They attempted to hide the spill from the coast guard but were unsuccessful. The charge each received carried a maximum penalty of $250,000 and 5 years prison time. Monitoring is expensive so it is done in the most efficient manner. Low risk ships or those less likely to cause spill are monitored less, while those that pose more risk are highly monitored. This is done based on the vessel history as it relates to oil spill events.  History can also determine penalties; a ship with a record of low compliance is likely to be subject to higher penalties. Also ships that do not report spills pay higher penalties as well.

Self reporting is an approach taken to cut government spending on monitoring. There is a list for ships that have been found to be out of compliance. The operators of such vessels tend to make a greater effort to self report, after being caught, in an attempt to regain the trust of the government and be removed from the list.

Figure 2: Alaska Oil Spill Civil Penalty Schedule
Environment	Freshwater	Marine	Public Land
Critical	US$10.00/gal US$2,940/tonne	US$2.50/gal US$735/tonne	US$1.00/gal US$294/tonne
Very sensitive	N/A	N/A	US$0.75/gal US$221/tonne
Sensitive	US$5.00/gal US$1,470/tonne	US$2.00/gal US$588/tonne	US$0.50/gal US$147/tonne
Without significant resources	US$1.00/gal US$294/tonne	US$1.00/gal US$294/tonne	US$0.25/gal US$74/tonne
The civil penalties are multiplied by the oil property factors as per figure 3.

Figure 3; Alaska Oil Property Penalty Modifying Factors
Property	Degree	Factor
Toxicity	Highly toxic	1.0
	Moderately toxic	0.75
	Less toxic	0.50
	Relatively nontoxic	0.25
Degradability	Low degradability	1.0
	Moderate degradability	0.5
	High degradability	0.25
Dispensability	High dispersibility	0.15
	Moderate dispersibility	0.50
	Low dispersibilty	1.0

Tables taken from A Worlwide Review of Marine Oil Spill Fines and Penalties 2003.

How would you decide the size of the penalty to be paid? Well, one of the methods used is to charge a price per liter/s or gallon/s of oil in an oil spill (Etkin, 2003). For a company like British petroleum that has paid billions in penalties one could only imagine the size of their spills.

Apart from legal deterrence of oil spills there is also a technical approach involving the designing of oil tankers to limit the chance of spills. One such design is the double hull oil tanker. As the name implies it has two hulls and a space separating both. The outer hull is on the sea, if this hull is breached no spill occurs as opposed to a single hull vessel. In 1992 the MARPOL Convention was amended so that all newly constructed ships would have a double hull (NOAA, 2016). In my opinion such a design should have been used from the inception of oil transport over the ocean.  

image taken from NOAA

An  illustration of damage done to the outer hull of an  vessel

Overall these approaches have proven to be effective in the reduction of oil spills, so much, that one can say that we have a good grasp of the concept of sustainable development.

References 

Mark A.Cohen. 2009, Oil Spills: The Deterrent Effects of Monitoring, Enforcement, Public Information, Resources for the future, 

Retrieved from  http://www.rff.org/blog/2009/oil-spills-deterrent-effects-monitoring-enforcement-and-public-information

Stan, Parker August 2016," Tanker Engineers Admit Hiding Oil dump From Coast Guard". Law 360, Retireved from  http://www.law360.com/articles/827716/tanker-engineers-admit-hiding-oil-dump-from-coast-guard

Dagmar, Schmidt Etkin. 2003, A Worlwide Review of Marine Oil Spill Fines and Penalties, Retrieved from  http://www.environmental-research.com/erc_papers/ERC_paper_10.pdf

NOAA 2016. A Final Farewell to Oil Tankers with Single Hulls, Office of Response and Restoration, Retrieved from http://response.restoration.noaa.gov/about/media/final-farewell-oil-tankers-single-hulls.html