Beach Survey Updates
- 2/22, Initial beach survey, Little South America
- 2/24-2/28, Airport Beach, Front Beach (Iliuliuk Bay), Summer Bay, Wide Bay, and the Dutch Harbor spit
- 3/1-3/4, Front Beach, Little South America, Wide Bay, and Airport Beach
- 3/4-3/8, Dutch Harbor Spit, Front Beach, and Little South America
- 3/8-3/15, Front Beach, Little South America, Wide Bay, and Airport Beach
- 3/15-3/20, Airport Beach, Front Beach (Iliuliuk Bay), Summer Bay, Wide Bay, and the Dutch Harbor spit
Beach Survey Update #1
On 2/22/05, a beach survey was conducted in Little South America to test the potential utility of this technique in monitoring indicator beaches in Unalaska Bay. Because tow net sampling data seems to have leveled off (no statistically significant change in encounter rate since mid-January), the beach surveys have been proposed as an alternate means for monitoring the bay for any changes in tarball concentration. The 2/22 beach survey resulted in the detection of a number of scattered tarballs ranging in size from a pea to a dollar bill. Tow net surveys in Captain’s Bay have shown no oil detection during the past few weeks. This preliminary data suggests that beach surveys might be a more sensitive detection method. Indicator beach segments in Wide Bay, Airport Beach, Summer Bay, Iliuliuk Bay, Dutch Harbor Spit, and Little South America will be surveyed regularly to watch for signs of new tarballs washing ashore. Tarballs that are observed on the beaches will be documented and, if feasible, removed for disposal.
Beach Survey Update #2
On 2/24/05, the Fisheries Work Group met and endorsed a winter sampling plan that calls for the gradual phase-out of tow net sampling and increased reliance on tar ball beach surveys to monitor Unalaska Bay for the presence and abundance of tar balls. An initial beach survey was completed at Little South America on 2/22/05, and based on that survey, a protocol was developed by the Sampling Group with input from the state, the Coast Guard, and the RP. The protocol calls for an initial survey at each of six designated survey beaches. During the initial survey, tar ball observations will be recorded (photographs & waypoints) and mapped, and then they will be removed from the beach for disposal. During subsequent visits (each site will be surveyed every 2-3 days), tar ball encounters will be recorded as possible evidence of “new” oiling. Beach survey segments are located in known collector areas in Little South America, Airport Beach, Front Beach (Iliuliuk Bay), Summer Bay, Wide Bay, and the Dutch Harbor spit.
On 2/25/05, an initial survey was conducted on Airport beach. Approximately 64 tar balls were observed along one segment, and approximately 11 tar balls along another. All were documented and collected for disposal.
On 2/26/05, initial surveys were conducted on Front Beach, Summer Bay, and the spit. No tar balls were observed at the spit. A few isolated tar balls were observed on Front Beach. All but one had the appearance of asphalt and it was speculated that they might be of a different origin than other tar balls recently observed. More than 60 tar balls were observed in Summer Bay, some appearing to be “fresh.”
On 2/23/05, an initial survey was conducted on Wide Bay beach and no tar balls were observed. On 2/2705 a second survey was conducted and 3 or 4 tar balls, that appeared to be relatively fresh, were observed and removed. The Wide Bay beach survey will be conducted regularly by the SOSC and RP representatives on overflights.
Beach Survey Update #3
Photo 3-1. Fresh tarball, Little South America.
Tar ball beach surveys have been conducted daily since 3/1/05. On 3/1/05, the beach survey team returned to Little South America to remove tarballs that had been observed on earlier beach walks. Approximately 45 tar balls (which had been reported a week prior) were removed from the beach.
On 3/2, beach surveys were conducted at Summer Bay and Front Beach. No new tar balls were observed.
On 3/3, beach surveys were conducted at Little South America, Wide Bay, and Airport Beach. A few tar balls were observed at Little South America, but the beach survey team suspected that most of these were tar balls that had been missed on the 3/1 survey due to low visibility (rain), with the exception of one tar ball that appeared “fresh” (Photo 3-1). One tar ball was observed at Airport Beach. There were no oil observations at Wide Bay.
Photo 3-2. Airport Beach
Attached are several photos that show the beach survey technique. We have selected short beach segments on each of the 6 beaches, and these same segments are surveyed every other day or so. First, the surveying team slowly moves down the beach, zig-zagging, and uses surveyor flags to mark every observed tar ball. Then, they stop at a designated photo location and take a photo of the beach, showing the basic distribution of tar balls (Photo 3-2). This not only informs on the quantity but on the general distribution (tide line). This information will presumably be useful in distinguishing whether tar balls observed on subsequent trips may have been overlooked during the initial survey (as reported for Little South America 3/3) or whether they may be from a new event. After the entire segment has been walked & the photograph taken, the survey team then reverses their course and stops at each flag, takes a waypoint, and photographs the GPS unit and tarball (Photo 3-3). Finally, the tar ball is cleaned off the beach, to the extent practical, and samples are occasionally taken for archive or lab analysis.
Photo 3-3. Airport Beach, 2/25/2005
Beach Survey Update #4
On 3/4/05, tarball beach surveys were conducted at the Spit, Front Beach, and Little South America. One tarball that appeared to be new was observed on Little South America and removed from the beach (Photo 4-1).
On 3/5/05, the passive sampling devices (PSD) in Unalaska Bay were checked and reset. No oil was observed on any of the PSDs. A beach survey was conducted at Wide Bay in conjunction with an overflight. Oiled tarballs were observed in the upper intertidal area and in the lower intertidal area. The tarballs in the lower intertidal (Photo 4-2) area appeared to be “fresher” than those higher up along the tide line (Photo 4-3).
On 3/6/05, beach surveys were conducted at Summer Bay and Little South America. At Summer Bay, 4 small tarballs (1-2 cm) were observed (Photo 4-4). At Little South America, 20-30 tarballs were observed, and these are believed to be new (i.e. were not present during the previous survey on 3/4/05). (Photo 4-5 and 4-6)
Beach Survey Update #5
On 3/8/05, beach surveys were conducted at Airport Beach and Front Beach, with no oil observed at either location. A large tar patty was observed at Little South America – it was located above the high tide line in a sorting tray, which led members of the survey team to question its origin. (Photo 5-1)
On 3/9/05, a beach survey was conducted at Spit Beach. No oil was observed, and no additional beach surveys were conducted due to the tide cycle.
On 3/10/05, a beach survey was conducted as Summer Bay. No oil was observed.
On 3/11/05, a beach survey was conducted at Wide Bay and approximately 325 weathered tarballs, most of them between 1mm and 4mm in size, were collected. (Photos 5-2, 5-3, 5-4)
On 3/12/05, a beach survey was conducted at Little South America, and approximately 16 tarballs were observed, as well as an area of “splattered” oil (Photo 5-5)
On 3/13/05, beach surveys were conducted at Airport Beach and Front Beach, with no oil observed at either location.
On 3/14/05, beach surveys were conducted at Summer Bay and Spit Beach, with no oil observed at either location.
Beach Survey Update #6
On 3/17/05, beach surveys were conducted at Little South America and Front Beach. No oil was observed at Front Beach. 1 tarball, approximately 5 cm, was observed at Little South America. Photo attached of the 3/17 tar ball and 2 of the tow net observations from 3/16. (Photo 6-1)
On 3/18/05, beach surveys were conducted at Summer Bay and Airport Beach. No tarballs were observed.
On 3/19/05, a beach survey was conducted at Wide Bay. 5 tarballs were observed. Photo attached. (Photo 6-2)
On 3/20/05, beach surveys were conducted at the Spit and Little South America. No oil was observed at the Spit. 2 tarballs and a 1 meter area of “splatter” (with 2-5% coverage) were observed at Little South America. Photo attached. (Photo 6-3)
On 3/21/05, beach surveys were conducted at Front Beach and Airport Beach. No oil was observed at either location.
Today (3/22/05), beach surveys were scheduled for Wide Bay, Summer Bay, and the Spit, weather permitting. Results are not yet in.
Tomorrow (3/23/05), the final beach surveys will be conducted at Little South America and Front Beach. Thursday (3/24/05), the passive sampling devices in Unalaska Bay will be checked for the final time and removed.
Chris Hall (Polaris)and Tom DeRuyter (ADEC) conducting a beach survey.
Photo 6-1. Photographs of the oil found in Unalaska Bay to 3/18/2005.
Photo 6-2. Tarballs were observed during a beach survey was conducted at Wide Bay 3/19/2005.
Photo 6-3. Tarballs and a 1 meter area of “splatter” (with 2-5% coverage) observed during a beach survey conducted 3/20/2005 at Little South America.