Leewards Cruise #19 
Census and observations on Hawaiian Monk Seal Monachus schauinslandi. 
Pearl & Hermes Reef, Laysan and Lisianski Islands, 31 May - 11 June 1967 
A minimal amount of time was devoted to the seal surveys. On Pearl & 
Hermes the surveys were taken during the first day on the islands, but on 
Laysan and Lisianski the surveys were made on the last day of the visit. 
Thus, due to disturbance, counts on the latter islands are low. Counts on 
Pearl & Hermes and Lisianski do not completely distinguish between pups in 
postnatal pelage and yearlings. The failure to distinguish between these 
two age classes was caused by finding tagged animals of both age groups 
carrying tags of the same numerical series. It was first assumed that all 
had been tagged as pups and thus were the same age, but this later proved 
to be false. For some of tnese animals sufficient notes were taken at 
time of observation to later distinguish between the age groups. 
* 
Twenty-four pups in natal pelage were tagged on the islands visited 
(Table 5) and 21 returns were taken (Table 4). Two skulls were obtained 
from dead, putrified adults on Laysan Island. An additional dead adult 
was seen on Laysan. 
DISCUSSION 
The discussion is primarily an extension of K. C. Balcomb’s report 
on Monachus prepared after the June 10-22, 1966 , visit to Laysan and 
Lisianski Islands. 
Feeding and Hauling Behavior 
Rice (1964) noted that on moonlight nights there were only adult fe¬ 
males with pups on the beach. He concluded from this and other evidence 
that the animals feed at night. During Balcomb’s surveys and again on 
this survey we noted many adults on the beach at night. Our visits were 
primarily during periods of dark moon. During dark-moon periods, the 
animals probably feed in the early mornings while the scattering layer is 
still near the surface in pelagic waters, and food species on the reef are 
out of hiding. 
On 7 June during our stay on Lisianski, a storm blew up with heavy 
winds from the northwest. During the day and night that this blow con¬ 
tinued, seals hauled out on the beach far back into the Scaevola fringe. 
Some of these animals were noted at different times during the night of 
6-7 June, and again throughout the day of 7 June (except for a period when 
the survey party left the island) and again on the night of 7 June. Dur¬ 
ing this entire time, many of the animals stayed in the Scaevola fringe, 
not leaving until early morning on 8 June (presumably to feed). Do these 
animals commonly refrain from feeding over long periods during the winter 
