Oil Look-Alikes

All That Sheens May Not Be Oil…or Tar Balls, Either

By Bill Mahan, Florida Sea Grant Agent, County Extension Director, Franklin/UF IFAS Extension Program

Tunicates and skate egg cases can bear a strong resemblance to tar balls.

From left: A black tunicate, colonial tunicate, and a skate egg case have often been mistaken for tar balls (right) on Florida shores. Sources: Bryan Fluech (Florida Sea Grant), Andrew Diller (Florida Sea Grant), NOAA

As a result of the BP Deepwater Horizon oil spill, anyone out boating in the Gulf of Mexico region or walking the beach is keeping an eye out for oil.

In most cases the person reports their “oil” sighting to the county’s Emergency Operations Center (EOC) with information on the date, time, place and what they saw. This is exactly what you should do if you see something you believe is related to the oil spill. Once the EOC receives a report of oil sheen, tar balls, or chocolate mousse, the EOC will notify the State EOC. Depending on the location of the report, a boat, plane or Shoreline Cleanup Assessment Technique (SCAT) team will be sent to the site to investigate, and to confirm or deny the presence of any oil product.

This reporting and verification system is in place to help reduce the number of rumors floating around about the oil sightings.

Where the system seems to be leaking, however, is that individuals and the local media reporting a possible oil sighting aren’t waiting for verification. Instead, they react to hearing the original sighting report, or that a boat, plane, or SCAT Team has been sent to investigate the report. The result has been a lot of unnecessary panic and rumors.

Here’s one example. As of July 1, there have been 19 State Watch and 81 Recon Reports of “BP oil spill product” called-in to Franklin County’s EOC . Each report has been investigated and none has been confirmed to be related to the BP oil spill. In fact, the cause of many of the sightings has turned out to be natural biological activities caused by Mother Nature herself.

So, people need to realize that not all sheen on the water, dark spots or blobs on the beach, and foamy or frothy material floating around in the water are caused by oil. In fact, Mother Nature produces these oil look-alikes all the time. This is especially true this time of the year, when our warm Gulf water is biologically active and productive.

Let’s take a look at some of Mother Nature’s look-alike oil spill creations:

Oily Sheen on the Water’s Surface A silvery or rainbow colored sheen on the water surface may be from a petroleum product. However, it may also be caused by natural events such as the presence of iron, decomposition of organic matter, or the presence of certain types of bacteria. Naturally occurring sheens are usually silver, or relatively dull in color that if disturbed, will break up into a number of small patches of sheen. Petroleum sheens on the other hand, tend to be shiny and rainbow-colored. If disturbed; the patches of oil will float back together.
Foam Lines/Mousse Oil, or sheen oriented in lines, or streaks floating on the water surface can easily be confused with the vegetative scum that can collect in tidal convergence lines or “tidelines.” Sometimes called streaks, stringers, or fingers, they are commonly found floating in near and offshore Gulf waters. They are usually just a collection of seagrasses, seaweeds and protein scum or foam that is being moved around by the tides and wind. Tar Balls A general description of a tar ball is weathered oil that has formed a pliable ball. They vary in size from a pinhead to about a foot across. Sheen may or may not be present around them. At this time, we have had a number of confirmed tar ball reports in the Florida Panhandle Region from Bay to Escambia County. However, before real tar balls were washing ashore, initial tar ball reports from Destin, upon examination, were identified as skate egg cases. Also, sea pork, a colonial type of sea squirt, pieces of peat and small sea cucumbers have been reported as possible tar balls in Panhandle counties.

Dark, Oil-like Patches of Sand on the Beach Several reports of black oil-like patches on the beach have been reported in Franklin County. When investigated, the dark patches of sand were found to be caused by ‘June Grass;’ clumps of sargassum and seagrass, or several different types of seaweed, that wash up on our local beaches. Although ‘June Grass’ can wash up on our beaches any time of the year, it typically begins washing ashore in large clumps in June, thus its name. In addition, these seaweeds and seagrass can break up into small dark particles as they are swept back and forth by wave action in the intertidal zone, leaving behind an area of dark-colored, stained sand.

Other Sightings/Rumors

In the Destin area in early May, a common rumor making the rounds was that sharp glassy fragments washing up on local beaches were fiberglass remains of the booms used to collect the oil out in the Gulf. When investigated, the fragments were found to be the exoskeletons of an animal called a pteropod, commonly called sea butterflies. These tiny marine snails lose their shells when they die. When the shells are washed ashore, the pointed part of the shell can prick people’s feet if they step on them. However, they pose no threat to people.

So what should you do if you see something that might be related to the oil spill?

By all means, please report it to your local EOC. Provide them with as much information as possible about when, where and what you saw. Then sit back and wait to hear if your sighting is confirmed as oil from the Deepwater Horizon spill, or it is something else. Until you receive confirmation, the last thing you should do is spread a rumor around either verbally, or via a social network, like Facebook, or Twitter. It makes absolutely no sense to spread a rumor around that can get people upset or worried. Be patient and wait to hear the investigation result of the sighting you reported.