Preassessment Data Report #4:

Results of a Drift Experiment to Estimate Seabird Carcass Deposition on
Beaches at Unalaska Island, Alaska, in the Vicinity of the Wreck

of the M/V *Selendang Ayu*

![](media/image1.jpeg){width="6.497916666666667in"
height="4.872916666666667in"}

Drift blocks washed ashore in Skan Bay, January 8, 2005

G. V. Byrd^1^

J. H. Reynolds^2^

*^1^U. S. Fish and Wildlife Service, Alaska Maritime National Wildlife
Refuge, 95 Sterling Highway, Suite 1, Homer, AK 99603*

*^2^U. S. Fish and Wildlife Service, Division of Natural Resources,
MS-221, 1011 E. Tudor Road, Anchorage, AK 99503*

**INTRODUCTION**

On 8 December 2004, the Selendang Ayu ran aground and broke in half in
rough seas off Unalaska Island, Alaska (53°38\'N, 167° 07\'W). An
estimated 354,218 gallons of oil (339,538 gallons of bunker oil \[IFO
380\] and 14,680 gallons of marine diesel and miscellaneous oils) were
released. Estimates of the number of marine birds killed by the spill
depend on variables such as the proportion of birds killed that actually
wash ashore. This variable is typically estimated by using drift blocks
to simulate carcasses (e.g., Flint and Fowler 1998).

Drift blocks were deployed from the M/V *Tiˆlaˆ*, which arrived in the
area December 23, 2004. The drift blocks were released at the first
subsequent opportunity when wind directions were similar to those at the
time of the wreck. Recovery of drift blocks during beach surveys for
carcasses and oil are summarized here.

**METHODS**

[Drift Blocks]{.underline}

Drift blocks were made of wood with dimensions: 4"x 4" x 8" \--
approximately 10 cm x 10 cm x 20 cm and weighted to simulate king eiders
(Figure 2). The blocks were painted orange to facilitate relocation on
beaches, and each had a unique number and a tag indicating that anyone
finding a block should contact the U.S. Fish and Wildlife Service (FWS)
for a reward.

[Deployment]{.underline}

On January 4, 2005, between 11:30-11:50h, Jeffrey C. Williams and the
crew aboard the M/V *Tiˆlaˆ* released 165 drift blocks. Blocks were
deployed in nine groups ranging from 8 to 40 blocks each to approximate
natural distributions of major species of birds at risk: for example, a
group of 40 was deployed to simulate species that form dense flocks like
black scoters (*melanitta nigra*) or crested auklets (*Aethia
cristatella*) and small bunches of 8 - 10 were deployed to approximate
other species of waterbirds. Blocks were deployed along a 2 km-long
transect, stretching approximately 1 to 3 km northeast of the Selendang
Ayu wreck (Figure 2).

At the time of deployment the wind was WNW at 20-25 knots and the swell
was NW at 8 ft. Although the wind direction was roughly onshore, similar
to the conditions at the time of the spill, the wind velocity and sea
state were not as extreme. Nevertheless, January 4 was the first
opportunity to deploy blocks under on shore wind conditions, and the
conditions during deployment were the closest conditions to those at the
time of the wreck since the arrival of the M/V *Tiˆlaˆ* in the area. The
wind and swell continued from that direction for 24-36 hours after the
blocks were deployed, but by mid-day January 6 the wind had changed to
SE 20-30 knots (offshore) and these conditions continued for several
days thereafter.

All personnel working on beaches in the spill area were informed, via
both the Unified Command and community meetings, of the deployment and
how to report recovered blocks. A reward was offered for recovered
blocks.

[Beach Surveys for Drift Blocks]{.underline}

Drift block recovery occurred as part of the beach surveys for oiled
wildlife carcasses. The survey region covered the geographic extent of
beaches known at that time to have been oiled from the wreck of the
*Selendang Ayu*: the north shore of Makushin Bay to Pumicestone Bay
(Figure 1).

Two types of beach surveys were conducted: rigorous, replicate surveys
of sample beaches to estimate the number of oiled wildlife carcasses in
the area, conducted by FWS crews from the M/V *Tiˆlaˆ* (Table 1), and
single visit surveys of beaches to document the extent of oiling and
opportunistically collect oiled wildlife carcasses, conducted by
pre-SCAT crews, known as Rapid Assessment Teams (Table 2). Survey teams
retrieved any blocks they discovered (Figure 2). For each block, all
beach crews were instructed to record the beach segment, date, block
number, and whether the block was visibly oiled or not.

The M/V *Tiˆlaˆ* survey crew periodically revisited a set of beaches to
detect newly deposited blocks and thus allow estimation of deposition
rate (Table 1). Probability of block recovery, combining both deposition
and detection, were estimated using only observations of blocks made
within 14 days of deployment since murre carcasses are estimated to sink
within 14 days (Wiese 2003). Confidence intervals for the recovery
probability were calculated using the method based on the relationship
between the F distribution and the binomial distribution Zar (1996, p
524). Blocks recovered on single visit surveys by pre-SCAT teams and
others were to be included under the assumption that a block could have
washed ashore within 14 days and remained on the beach indefinitely
until discovery.

**RESULTS**

At 20:30h on January 4, approximately 11 hours after the blocks were
deployed, personnel aboard the M/V *Commitment* reported that orange
drift blocks were seen "everywhere" in the water in Skan Bay (e.g.,
Figure 3a). Within the fourteen days following deployment, 165 beach
surveys were conducted: 77 by the M/V *Tiˆlaˆ* crew (Table 1), 88 by the
pre-SCAT teams and others (Table 2, ignoring the M/V *Tiˆlaˆ* surveys
identified in Table 1).

Blocks were first found ashore on January 8 (Table 1).

> "We found 16 drift blocks on SKS 18 segment 4. The blocks on the beach
> were easily observed while we were in a skiff approaching the shore.
> All 16 blocks were oiled and we disposed of them as oily waste after
> recording the ID numbers and location. After our beach surveys, I
> surveyed the shoreline of SKS 10,11,12,18, and SKN 1,2,15 from a skiff
> looking for more drift blocks. I found a small cluster of 10 blocks
> several hundred meters up the beach from SKS 18 segment 4 \[still in
> SKS 18\]. I recorded the numbers, but left the blocks on the beach
> since they were not on our beach survey segments and are susceptible
> to rewash. Only 1 of these blocks found off our survey beach segment 4
> (359) was oiled." (J.C. Williams log on January 8, 2005, Williams
> 2005).

The latter group of 10 blocks referred to by Williams was subsequently
recovered 8 hours later by another beach oil survey crew from the
support vessel M/V *Commitment*. No other block recoveries within the 14
day window following deployment were reported.

Block deposition rate could not be calculated due to the lack of further
recoveries. Block recovery probability was estimated as 16% = 26 / 165
with a 95% confidence interval of (11%, 22%). Block recovery probability
was specifically defined as the probability that a drift block released
near the wreck was deposited on a surveyed beach in the area known, at
the time, to have been oiled and subsequently recovered during surveys
within the 14 day window. The probability that a recovered block was
visibly oiled was estimated as 65% = 17 / 26 with 95% confidence
interval (48%, 80%).

Some blocks that drifted away from Unalaska Island were later found
throughout the Aleutians:

Block \# 394 was found at Adak Island on 31 May 2005;

Block \# 490 was reported found on 12 July 2005 from Walt Bay on Atka
Island;

Block \# 417 was found 31 December 2005 at the southern tip of Umnak
Island; and

Block \# 379 was found 7 January 2006 on the east side of Shemya Island.

**DISCUSSION**

Carcass deposition on beaches following an oil spill is influenced by
many factors such as wind, current direction and velocity. The recovery
rate of objects experimentally dropped at sea, i.e. carcasses or blocks,
and recovered in subsequent beach searches is highly variable and
generally small (Hope-Jones et al, 1970; Bibby and Lloyd, 1977; Piatt et
al, 1990; Threlfall and Piatt, 1983; Hlady and Burger, 1993; Piatt and
Ford, 1996). A review of experimental deposition studies incorporating
systematic beach surveys reported recovery rates ranging from 0-59%,
with a median of 11% (Piatt and Ford 1996).

The drift block release was relatively near shore, similar to the source
of the oil. The release was conducted during the first opportunity in
which wind and sea conditions were similar to that at the time of the
spill. Conditions were similar in direction but not as extreme in
magnitude (wind velocity, sea state) as during the spill.

Using the block recovery estimate as an estimate of deposition rate
requires assuming that block persistence and detection are both 1.0,
otherwise the recovery rate estimate of 16% *underestimates* the
deposition rate. While block persistence was likely high, as they would
not be removed by scavengers, it was likely not perfect as they were
susceptible to rewash. Block detection was also likely high due to
coloring and unique shape, but less than perfect due to reality of beach
surveys. The recovery estimate also does not account for the uneven
distribution of survey effort across beaches within the spill zone
following drift block deployment (Figure 2, Tables 1 and 2).

The beaches where blocks were found were directly down wind from the
point of release. This distribution of recoveries fits with previous
studies that concluded wind direction was a primary determinant of
carcass drift (Hlady and Burger 1993, Flint and Fowler 1998). All
recoveries were located on catchment beaches (see Table 2), indicating
that deposition was probably influenced by wind and local currents
(Flint and Fowler 1998).

**ACKNOWLEDGEMENTS**

Paul Flint made essential contributions to this report. Tremendous
thanks to the following individuals for the their assistance in
implementing this study and in reviewing the report: the crew of the M/V
*Tiˆlaˆ* - Kevin Bell, Dan McNulty, Dennis Haunschild, John Faris, Dan
Erickson, Joe Isenhour, Bob Ward, Eric Nelson; Jeff Williams, Leslie
Slater, Becky Howard, Bill Schaff, Greg McClelland, Ty Wyatt, Janis
Krukof, Kent Sundseth, Jeff Lewis, [C]{.underline}ris Dippel, Andy
Aderman, Don Dragoo, Arthur Kettle, Greg Thomson, Steve Kendall, Gary
Wheeler, Pat Walsh, Fred Broerman, Ken Gates, Kristine Sowl, Thomas
Siekaniec, Clay McDermott, Delia Person, Michael Winfree, Suzann
Speckman, Merban Cebrian, Jennie Wetzel, Ingrid Harrald, and especially
Laurie Daniel.

**REFERENCES**

Bibby, C.J. and Lloyd, C.S. 1977. Experiments to determine the fate of
dead birds at sea. Biological Conservation 12: 295-309.

Flint, P.L. and A.C. Fowler 1998. A Drift Experiment to Assess the
Influence of Wind on Recovery of Oiled Seabirds on St. Paul Island,
Alaska. Marine Pollution Bulletin 36: 165-166.

Hlady, D.A. and Burger, A.E. 1993. Drift-block experiments to analyze
the mortality of oiled seabirds off Vancouver Island, British Columbia.
Marine Pollution Bulletin 26: 495-500.

Hope-Jones, P., G. Howells, E.I.S. Rees, and J. Wilson 1970. Effect of
the 'Hamilton Trader' oil on birds in the Irish Sea in May 1969. British
Birds 63: 97-110.

Piatt, J.F. and R.G. Ford. 1996, How many seabirds were killed by the
*Exxon Valdez* oil spill?: pp. 712--719. *In* S. D. Rice, R. B. Spies,
D. A. Wolfe, and B. A. Wright \[EDS.\], Proceedings of the *Exxon
Valdez* oil spill symposium. Am. Fisheries Soc. Symposium 18, Bethesda,
MD.

Piatt, J.F., C.J. Lensink, W. Butler, M. Kendziorek and D.R. Nysewander
1990. Immediate impact of the Exxon Valdez oil spill on marine birds.
Auk 107: 387-397.

Threlfall, W. and J.F. Piatt 1983. Assessment of offshore oil mortality
and corpse drift experiments. Unpublished report for Mobil Oil Canada,
Ltd., St. John's Memorial University, Newfoundland.

Weise, F.K. 2003. Sinking rates of dead birds: improving estimates of
seabird mortality due to oiling. Marine Ornithology 31:65-70.

Williams, J.C. 2005. Activity log of damage pre-assessment activities in
response to the wreck of the M/V Selendang Ayu, 22 December 2004 -15
January 2005. U.S. Fish and Wildl. Rep. AMNWR 05/02. Homer, AK.

Zar, J. 1996. Biostatistical Analysis (3^rd^ ed.). Prentice Hall, Upper
Saddle River, New Jersey.

**Figure 1.** Drift Block Search Areas post-deployment

![](media/image2.jpeg){width="6.770833333333333in"
height="4.284722222222222in"}

**Table 1.** Fourteen day replicate survey effort by M/V *Tiˆlaˆ* crew
following drift block deployment near the Selendang Ayu wreck, January
2005. A blank in the Comments column means ground survey conducted but
no items found.

  -------------------------------------------------------------------------
  **Beach Segment** **Date**   **Survey Crew**   **Comments**
  ----------------- ---------- ----------------- --------------------------
  SKN 8             6 Jan      Tiglax            

  SKN 11            6 Jan      Tiglax            

  SKN 15            6 Jan      Tiglax            

  SPR 9             7 Jan      Tiglax            Soybeans on beach

  SPR 10            7 Jan      Tiglax            Soybeans on beach

  SPR 11            7 Jan      Tiglax            Soybeans on beach

  SPR 13            7 Jan      Tiglax            

  KFP 5             7 Jan      Tiglax            

  KFP 9             7 Jan      Tiglax            

  KFP 10            7 Jan      Tiglax            

  KFP 11            7 Jan      Tiglax            

  PMS 5             8 Jan      Tiglax            

  PMS 6             8 Jan      Tiglax            

  PMS 8             8 Jan      Tiglax            

  PMN 4             8 Jan      Tiglax            

  PMN 10            8 Jan      Tiglax            

  PMN 14            8 Jan      Tiglax            

  SKS 12            8 Jan      Tiglax            

  SKS 18            8 Jan      Tiglax            16 drift blocks found on
                                                 beach, recorded and
                                                 collected.

  SKS 10            8 Jan      Tiglax            Surveyed by skiff just
                                                 offshore

  SKS 11            8 Jan      Tiglax            Surveyed by skiff just
                                                 offshore

  SKS 12            8 Jan      Tiglax            Surveyed by skiff just
                                                 offshore

  SKS 18            8 Jan      Tiglax            Surveyed by skiff just
                                                 offshore

  SKN 1             8 Jan      Tiglax            Surveyed by skiff just
                                                 offshore

  SKN 2             8 Jan      Tiglax            Surveyed by skiff just
                                                 offshore

  SKN 15            8 Jan      Tiglax            Surveyed by skiff just
                                                 offshore

  CNB 3             9 Jan      Tiglax            

  CNB 10            9 Jan      Tiglax            

  CNB 19            9 Jan      Tiglax            

  UDW 1             9 Jan      Tiglax            

  UDW 7             9 Jan      Tiglax            

  UDE 7             9 Jan      Tiglax            

  UDE 9             9 Jan      Tiglax            

  UDE 13            9 Jan      Tiglax            

  NGW 2             9 Jan      Tiglax            

  SKN 8             11 Jan     Tiglax            Replicate survey

  SKN 11            11 Jan     Tiglax            Replicate survey

  SKN 15            11 Jan     Tiglax            Replicate survey

  KFP 5             11 Jan     Tiglax            Replicate survey

  KFP 9             11 Jan     Tiglax            Replicate survey

  KFP 10            11 Jan     Tiglax            Replicate survey

  KFP 11            11 Jan     Tiglax            Replicate survey

  PTN 10            12 Jan     Tiglax            

  HMP 6             12 Jan     Tiglax            

  CNB 19            12 Jan     Tiglax            Replicate survey

  SPR 9             13 Jan     Tiglax            Replicate survey

  SPR 10            13 Jan     Tiglax            Replicate survey

  SPR 11            13 Jan     Tiglax            Replicate survey

  SPR 13            13 Jan     Tiglax            Replicate survey

  PMS 5             14 Jan     Tiglax            Replicate survey

  PMS 6             14 Jan     Tiglax            Replicate survey

  PMS 8             14 Jan     Tiglax            Replicate survey

  PMN 4             14 Jan     Tiglax            Replicate survey

  PMN 10            14 Jan     Tiglax            Replicate survey

  PMN 14            14 Jan     Tiglax            Replicate survey

  SKS 12            14 Jan     Tiglax            Replicate survey

  SKS 18            14 Jan     Tiglax            Replicate survey

  NGW 2             17 Jan     Tiglax            Replicate survey

  UDE 13            17 Jan     Tiglax            Replicate survey

  UDE 7             17 Jan     Tiglax            Replicate survey

  UDE 9             17 Jan     Tiglax            Replicate survey

  UDW1              17 Jan     Tiglax            Replicate survey

  UDW7              17 Jan     Tiglax            Replicate survey

  PMN 10            18 Jan     Tiglax            Replicate survey

  PMN 14            18 Jan     Tiglax            Replicate survey

  SKN 11            18 Jan     Tiglax            Replicate survey

  SKN 15            18 Jan     Tiglax            Replicate survey

  SKN 8             18 Jan     Tiglax            Replicate survey

  CNB 10            19 Jan     Tiglax            Replicate survey

  CNB 19            19 Jan     Tiglax            Replicate survey

  CNB 3             19 Jan     Tiglax            

  CNB 9             19 Jan     Tiglax            

  HMP 5             19 Jan     Tiglax            

  HMP 6             19 Jan     Tiglax            Replicate survey

  HMP 7             19 Jan     Tiglax            

  KFP 11            19 Jan     Tiglax            Replicate survey

  PTN 10            19 Jan     Tiglax            Replicate survey
  -------------------------------------------------------------------------

**Table 2.** Coastline segment classification based on observations from
the M/V *Tiˆlaˆ*, December 25-26, 2004 and drift block survey schedule,
January 4--19, 2005 (Figure 1).

  ----------------------------------------------------------------------------------
  **Map   **NOAA      **NOAA      **Beach     **Beach Type**           **Drift block
  No.**   section**   segment**   code^a^**                            search^b^**
  ------- ----------- ----------- ----------- ------------------------ -------------
  14      **VLC**     1           N           headland                 

  14      **VLC**     2           C/E         sand / cobble            

  14      **VLC**     3           N           cobble / boulder         

  14      **VLC**     4           E           headland                 

  14      **VLC**     5           C           sand                     

  14      **VLC**     6           E           sand                     

  14      **VLC**     7           E           sand                     

  14      **VLC**     8           N           inlet                    

  14      **VLC**     9           E           sand                     

  14      **VLC**     10          E           boulder                  

  13      **MKS**     1           P           sand & some boulder      

  13      **MKS**     2           P           sand                     

  13      **MKS**     3           P           sand                     

  13      **MKS**     4           N           sand                     

  13      **MKS**     5           P           sand                     

  13      **MKS**     6           P           sand                     

  13      **MKS**     7           P           sand                     

  13      **MKS**     8           P           sand & headland          

  13      **MKS**     9           P           sand & gravel            

  13      **MKS**     10          N                                    

  13      **MKS**     11          P           cobble & gravel          

  13      **MKS**     12          P           cobble                   

  13      **MKS**     13          N           bedrock                  

  13      **MKS**     14          N           bedrock                  

  13      **MKS**     15          N           bedrock                  

  13      **MKS**     16          E           small cobble beach       

  13      **MKS**     17          N                                    

  13      **MKS**     18          N/E         cobble / beach / cliff   

  12      **HMP**     1           N                                    

  12      **HMP**     2           P           cobble                   

  12      **HMP**     3           N                                    

  12      **HMP**     4           N                                    

  12      **HMP**     5           N                                    

  12      **HMP**     6           P           bedrock                  

  12      **HMP**     7           P                                    

  12      **HMP**     8           P           cobble                   

  12      **HMP**     9           N                                    

  12      **HMP**     10          P           cobble                   

  12      **HMP**     11          N           rocky outcrop            

  12      **HMP**     12          P           cobble                   

  12      **HMP**     13          P           boulder, bedrock         

  11      **PTN**     1           N                                    

  11      **PTN**     2           N                                    

  11      **PTN**     3           P           gravel / cobble          

  11      **PTN**     4           P           gravel / cobble          

  11      **PTN**     5           P                                    

  11      **PTN**     6           P                                    

  11      **PTN**     7           N                                    

  11      **PTN**     8           N                                    

  11      **PTN**     9           N                                    

  11      **PTN**     10          C           gravel / cobble          

  11      **PTN**     11          N                                    

  11      **PTN**     12          P           cobble / small boulders  

  11      **PTN**     13          P           cobble / small boulders  

  11      **PTN**     14          P           cobble / small boulders  

  11      **PTN**     15          P           cobble / small boulders  

  11      **PTS**     1           P           gravel / small boulders  

  11      **PTS**     2           P                                    

  11      **PTS**     3           P           cobble / small boulder   

  11      **PTS**     4           P           small boulder            

  11      **PTS**     5           N                                    

  11      **PTS**     6           N           creek                    

  11      **PTS**     7           P                                    

  11      **PTS**     8           N                                    

  11      **PTS**     9           N                                    

  11      **PTS**     10          N           creek                    

  11      **PTS**     11          N           creek                    

  11      **CNB**     1           P           small boulder /          
                                              vegetation               

  11      **CNB**     2           N           stream                   

  11      **CNB**     3           P                                    

  11      **CNB**     4           N           stream                   

  11      **CNB**     5           P                                    

  11      **CNB**     6           N           stream                   

  11      **CNB**     7           P                                    

  11      **CNB**     8           N           creek                    

  11      **CNB**     9           P           alluvial fan             

  11      **CNB**     10          P           alluvial fan             

  11      **CNB**     11          N           delta                    

  11      **CNB**     12          N           creek                    

  11      **CNB**     13          N           delta                    

  11      **CNB**     14          P                                    

  11      **CNB**     15          N                                    

  11      **CNB**     16          P           bedrock                  

  11      **CNB**     17          P           bedrock                  

  11      **CNB**     18          N           stream                   

  11      **CNB**     19          C           cobble                   

  11      **CNB**     20          P           boulder / small boulder  

  11      **CNB**     21          P           small boulder/cobble     

  11      **AND**     1           C           cobble                   

  11      **AND**     2           P           broken                   

  11      **AND**     3           N                                    

  11      **AND**     4           N                                    

  11      **AND**     5           P           boulder / cobble         

  11      **AND**     6           C           boulders                 

  11      **AND**     7           C           boulders / bedrock /     
                                              headlands                

  11      **AND**     8           P           boulder / cobble / small 
                                              headlands                

  10      **UDE**     1           N                                    

  10      **UDE**     2           N           stream                   

  10      **UDE**     3           P           cobble / gravel          

  10      **UDE**     4           P                                    

  10      **UDE**     5           N                                    

  10      **UDE**     6           N                                    

  10      **UDE**     7           P           cobble                   

  10      **UDE**     8           N           stream                   

  10      **UDE**     9           P           cobble                   

  10      **UDE**     10          P           cobble / gravel          

  10      **UDE**     11          N           stream                   

  10      **UDE**     12          P           narrow cobble / shale    

  10      **UDE**     13          P           gravel / cobble          

  10      **UDE**     14          P                                    

  10      **UDE**     15          N                                    

  10      **UDE**     16          P           gravel / cobble          

  9       **UDE**     17          P                                    

  9       **UDE**     18          N           creek                    

  9       **UDE**     19          P           gravel                   

  9       **UDE**     20          N           creek                    

  9       **UDE**     21          P           narrow cobble bedrock    

  9       **UDE**     22          C                                    

  9       **UDE**     23          N                                    

  9       **UDE**     24          N                                    

  10      **UDW**     1           P           boulder                  

  10      **UDW**     2           P           boulder                  

  10      **UDW**     3           not                                  
                                  evaluated                            

  10      **UDW**     4           P           bedrock                  

  10      **UDW**     5           P           bedrock                  

  10      **UDW**     6           N                                    

  10      **UDW**     7           P           small boulder            

  10      **UDW**     8           P                                    

  10      **NGE**     1           not                                  
                                  evaluated                            

  10      **NGE**     2           not                                  
                                  evaluated                            

  10      **NGE**     3           P                                    

  10      **NGE**     4           N           creek                    

  10      **NGE**     5           N                                    

  10      **NGE**     6           P           mix of cobble, bedrock,  
                                              boulders                 

  10      **NGE**     7           P           cobble / boulder         

  9       **NGW**     1           C           cobble                   

  9       **NGW**     2           P           cobble                   

  9       **NGW**     3           N           stream                   

  9       **NGW**     4           P           cobble                   

  9       **NGW**     5           P           cobble                   

  9       **NGW**     6           N           stream                   

  9       **NGW**     7           P           boulder, cobble, gravel  

  10      **NGW**     8           P           cobble                   

  10      **NGW**     9           N           stream                   

  10      **NGW**     10          P           cobble                   

  10      **NGW**     11          N           stream                   

  10      **NGW**     12          P                                    

  10      **NGW**     13          P                                    

  10      **NGW**     14          P                                    

  10      **NGW**     15          P                                    

  10      **NGW**     16          P                                    

  8       **KFP**     1           E           gravel, cobble           

  8       **KFP**     2           N           bedrock headland         

  8       **KFP**     3           N           bedrock headland         

  8       **KFP**     4           N           bedrock headland         

  8       **KFP**     5           C           cobble                   

  8       **KFP**     6           N           stream                   

  8       **KFP**     7           E           boulder                  

  8       **KFP**     8           E           boulder                  

  8       **KFP**     9           C           boulder                  

  8       **KFP**     10          E           boulder                  

  8       **KFP**     11          E           boulder                  

  8       **KFP**     12          E           boulder                  

  8       **KFP**     13          N           bedrock, headland        

  8       **KFP**     14          E           boulder                  

  8       **KFP**     15          E           cobble                   

  8       **KFP**     16          E           boulder                  

  8       **KFP**     17          E           cobble                   

  7       **SKN**     1           E           cobble, boulder          by skiff

  7       **SKN**     2           N           rocky islet              by skiff

  7       **SKN**     3           E           gravel, cobble large     
                                              boulder                  

  7       **SKN**     4           N           stream                   

  7       **SKN**     5           E           gravel                   

  7       **SKN**     6           N           bedrock headland         

  7       **SKN**     7           N           bedrock headland         

  7       **SKN**     8           C                                    

  7       **SKN**     9           N           bedrock headland         

  7       **SKN**     10          N           bedrock headland         

  7       **SKN**     11          C                                    

  7       **SKN**     12          N           bedrock headland         

  7       **SKN**     13          N           bedrock                  

  7       **SKN**     14          N           stream                   

  7       **SKN**     15          E           cobble boulder           by skiff

  7       **SKS**     1           E           cobble                   

  7       **SKS**     2           E           cobble                   

  7       **SKS**     3           E           cobble                   

  7       **SKS**     4           E           cobble                   

  7       **SKS**     5           N                                    

  7       **SKS**     6           E           cobble                   

  7       **SKS**     7           N                                    

  7       **SKS**     8           N           bedrock                  

  7       **SKS**     9           N           bedrock                  

  7       **SKS**     10          N           bedrock                  by skiff

  7       **SKS**     11          N           stream                   by skiff

  7       **SKS**     12          E           small boulders & bedrock by skiff

  7       **SKS**     13          P           gravel & bedrock         

  7       **SKS**     14          N           stream                   

  7       **SKS**     15          P           gravel & bedrock         

  7       **SKS**     16          N           bedrock outcrop          

  7       **SKS**     17          N           islet                    

  7       **SKS**     18          C           bedrock headland, cobble by skiff

  7       **SPR**     1           E           60%headland, 40% gravel  

  7       **SPR**     2           E           gravel                   

  7       **SPR**     3           N           stream                   

  7       **SPR**     4           E           gravel                   

  7       **SPR**     5           N           bedrock headland         

  7       **SPR**     6           N           bedrock headland         

  7       **SPR**     7           E           cobble                   

  7       **SPR**     8           N           islet                    

  7       **SPR**     9           E           bedrock headland         

  7       **SPR**     10          E           boulder                  

  7       **SPR**     11          E           boulder                  

  7       **SPR**     12          E           boulder                  

  7       **SPR**     13          E           boulder                  

  7       **SPR**     14          N           bedrock headland         

  5       **PMN**     1           N           cliffs/bedrock           

  5       **PMN**     2           E           sand/gravel              

  5       **PMN**     3           N           cliffs                   

  5       **PMN**     4           E           sand/gravel              

  5       **PMN**     5           N           stream                   

  5       **PMN**     6           E           mostly cliff             

  5       **PMN**     7           E           mostly bedrock           

  5       **PMN**     8           E           1/2 beaches, cobble      

  5       **PMN**     9           N           pointy bedrock           

  5       **PMN**     10          E           large boulders / cobble  

  5       **PMN**     11          E           gravel / cobble          

  5       **PMN**     12          E           bedrock, gravel          

  5       **PMN**     13          N           headland                 

  6       **PMN**     14          E           bedrock beach            

  6       **PMN**     15          E           bedrock beach            

  6       **PMN**     16          C           cobble                   

  6       **PMN**     17          N           cliffs                   

  6       **PMN**     18          E           gravel beach             

  6       **PMN**     19          N           cliffs                   

  6       **PMN**     20          N           islet                    

  6       **PMN**     21          N           stream                   

  6       **PMN**     22          N           bedrock cliffs           

  6       **PMN**     23          N           boulder beach            

  6       **PMN**     24          N           cliffs                   

  6       **PMN**     25          N           large boulders           

  6       **PMN**     26          N           headlands, large         
                                              boulders                 

  6       **PMN**     27          N           headlands, large         
                                              boulders, rockslides     

  6       **PMN**     28          N           bedrock headlands, large 
                                              boulders                 

  5       **PME**     1           P           cobble gravel            

  5       **PME**     2           N           islet                    

  5       **PME**     3           P           cobble / gravel          

  5       **PME**     4           N           islet                    

  5       **PME**     5           P           cobble / small rock      

  5       **PME**     6           P           cobble                   

  5       **PME**     7           N           stream                   

  5       **PME**     8           N           islet                    

  5       **PME**     9           P           delta                    

  5       **PME**     10          N           stream                   

  5       **PME**     11          N           islet                    

  5       **PME**     12          N           bedrock                  

  5       **PME**     13          N           bedrock                  

  5       **PME**     14          N           bedrock                  

  5       **PME**     15          N           bedrock                  

  5       **PME**     16          N                                    

  5       **PME**     17          N           bedrock                  

  5       **PME**     18          N           bedrock                  

  5       **PME**     19          N           bedrock                  

  5       **PME**     20          N           cliff                    

  4       **PMS**     1           E           boulder                  

  4       **PMS**     2           E           boulder                  

  4       **PMS**     3           N           landslides / large       
                                              boulders                 

  4       **PMS**     4           N           boulder / landslide /    
                                              cobble                   

  5       **PMS**     5           E           boulder / landslide /    
                                              cobble                   

  5       **PMS**     6           C           cobble / small boulder   

  5       **PMS**     7           N           stream                   

  5       **PMS**     8           N           headland                 

  5       **PMS**     9           N           stream                   

  5       **PMS**     10          C           small cobble             

  5       **PMS**     11          N           bedrock                  

  5       **PMS**     12          N           bedrock                  

  5       **PMS**     13          N           bedrock - steep / narrow 

  5       **PMS**     14          N           bedrock - steep / narrow 

  5       **PMS**     15          P           cobble / bedrock         

  5       **PMS**     16          P           cobble / gravel          

  5       **PMS**     17          N           stream                   

  5       **PMS**     18          N           islet                    

  5       **PMS**     19          N           bedrock - steep / narrow 

  5       **PMS**     20          P           cobble / gravel          

  5       **PMS**     21          P           cobble / gravel          
  ----------------------------------------------------------------------------------

^a^ [Beach Codes]{.underline}:

E = Exposed or high impact beaches (normally exposed to waves often with

steep angles indicating frequent impacts);

C = Catchment (beaches with areas where large amounts of debris had

accumulated);

P = Protected (not normally exposed to waves from the open sea);

N = No beach (cliffs or other unwalkable segments of coastline).

^b^ [Drift block search]{.underline}:

 = drift block search conducted, multiple 's indicate replicate
searches over

the time frame of January 4 -- 19, 2005.

**Figure 2.** Series of photographs illustrating the drift block
experiment

![](media/image3.jpeg){width="5.126388888888889in"
height="3.8555555555555556in"}

Drift blocks (4x4x8 inch) with identification tag specifying reporting
contact information

![](media/image4.jpeg){width="5.370833333333334in"
height="4.027777777777778in"}

A small group deployment of drift blocks in the vicinity of the
Selendang Ayu wreck.

![](media/image5.jpeg){width="2.9965277777777777in"
height="3.995833333333333in"}
![](media/image6.jpeg){width="2.9965277777777777in"
height="3.995833333333333in"}

Drift blocks washed up on shore in Skan Bay Tiˆlaˆ, beach survey crew,
Leslie Slater,

with the M/V Tiˆlaˆ**,** in background. recording and collecting beached
drift blocks.