The Hawaiian monk seal (Monachus schauinslandi) is one of three species of tropical seals in the world. The Caribbean monk seal (M. tropicalls) is thought to be extinct. The Mediterranean monk seal (M. monachus) is endangered with a population estimate of fewer than 500. The Hawaiian monk seal is endangered with a current population of approximately 1500 animals. Most of the Hawaiian seals reside on remote coral-sand atolls in the Northwestern Hawaiian Islands (NWHI), an area extending approximately 1000 miles from end to end.

The decline of the Hawaiian monk seals started in the 1800s when many were hunted for skins and oil. One account in 1859 recorded a ship with possibly 1500 seal skins aboard. The killing of seals extended into the 1900s when the fur and feather trade was flourishing.

The NWHI, to Midway, were designated a part of the National Wildlife Refuge System in 1940. The U.S. Fish and Wildlife Service administer the refuge. Kure Atoll, lying beyond Midway, is a State of Hawaii seabird sanctuary. These protective designations restricted access to the islands except for military and U.S. Coast Guard (USCG) activities at Kure Atoll, Midway Islands, and French Frigate Shoals (East and Tern Islands).

The recent decline of the Hawaiian monk seal (beach counts down 50% since the late 1950s) may be attributed to multiple factors, but humans by far are the main cause. Beach activities directly and indirectly of human origin (beach walking, dogs, vehicles on beaches, etc.) tend to keep mother seals and pups in the water, thereby exposing them to shark predation. Pregnant seals and those with pups are forced to reside on smaller, less-protected sand islands, thereby exposing them to weather elements as well as predators. The main predator of the monk seal is the tiger shark.

There are eight main breeding sites for the seals. Three of these have a history of human intervention. Tern Island at French Frigate Shoals was occupied by the USCG from 1952 to July 1979. Beach counts at Tern Island were never more than a few animals until the USCG left. Beach counts now average over 100 seals.

Kure Atoll, located near Midway, is the site of a USCG loran station which opened in 1960. It is usually staffed with 20-30 personnel. Monk seal births in the 1950s and 1960s of 30 pups per year declined to 9-10 in 1977-81, then to a low of only 1 pup in 1986.

The Midway population declined drastically during the 1960s and early 1970s when the human population there was over 2000. Beach counts dropped from over 100 seals to only a few animals.

Monk seal recovery planning was initiated in 1981 by the Protected Species Investigation of the National Marine Fisheries Service, Southwest Fisheries Science Center, Honolulu Laboratory. A top priority was the rebuilding of the seal population at the western end of the NWHI (Kure Atoll, Midway Islands, and Pearl and Hermes Reef).

The Head Start Project at Kure Atoll began in 1981 in an attempt to save that dwindling population. Female seal pups were collected after weaning and were placed in an enclosed sea and beach pen. They were fed live reef fish through the summer months and then released. This greatly increased their survival rate.

In 1984, a second program was initiated to add females to the Kure population. Undersized female pups (girth measurement less than 90 cm) were taken from French Frigate Shoals (an area of high seal density) and transported to Honolulu and held in saltwater tanks over the winter months, during which time they were "fattened" on herring. They were then flown to Kure Atoll and retained in the Head Start pen for a period of adaptation to foraging on their own. Release usually occurred after a period of 2-4 weeks.

In 1989, Sea Life Park, a large oceanarium on the island of Oahu, constructed a special habitat complex for Hawaiian monk seal adults and pups. An agreement with the National Marine Fisheries Service allowed Sea Life Park to care for the "rehab" pups over the winter months.

From 1989 to 1992, 16 pups have been rehabilitated for release. Because of the concern that certain diseases might be introduced in the "wild" population, strict quarantine regulations have been applied. Disinfectant foot baths were installed as well as separate clothing for handling the pups.

All arriving seals for rehabilitation undergo a standard screening protocol:

1.  physical examination

2.  blood drawn for CBC and chemistries

3.  fecal examination for parasites

4.  fecal culture for Salmonella,

5.  occult heartworm test

6.  serum canine distemper titer for IGG and IGM

7.  Leptospira serum titers for five serotypes

8.  Toxoplasma serum titers

The same health screening protocol is conducted on all existing seals within 2 weeks of departure.

The average weight of the 15 seals that were weighed upon arrival for rehabilitation was 79.9 lb (36.6 kg). One seal pup born on the North Shore of Oahu was collected after weaning and processed as a rehab. Her weight was 220 lb (100 kg), which was above average for a normal weaned monk seal pup. She was relocated to Kure 43 days after collection.

On arrival at Sea Life Park from French Frigate Shoals the pups are given electrolyte replacement fluid and started on force-feedings. Usually 1-2 lb of herring are initially given over two feedings with vitamin supplements. Within days to weeks, live fish are offered, usually pond-reared Tilapia. Various dead reef fish species are also offered.

Monk seal pups seem to start feeding on their own when they are good and ready! One thing is certain, it is not immediate. Thirteen pups took an average of 14.4 weeks (range, 1-34 weeks) to begin eating live fish. The average number of days from arrival to eating frozen herring was 17.2 weeks. This usually occurred 3 weeks after the pups started eating live fish. Two seals were not included in this study. One was born on Oahu and shipped to Kure before she started eating. The other pup is still being force-fed after 37 weeks in captivity.

Various protocols have been attempted to speed up this process, but to no avail (i.e., multiple feedings, various diets, and formula tube feedings, withholding food. and diazepam drug appetite stimulation). Force-feedings once or twice daily are now standardized and are the least labor intensive with the same results. Lengthy force-feeding periods prior to pups eating on their own have also been reported for elephant seal (Mirounga sp.) and Mediterranean monk seal pups. The pups gained weight rapidly after starting to eat frozen herring, and by release, most were eating 6-8 lb daily.

The average period of time spent at Sea Life Park was 8.5 to 12 months before the pups were shipped to Kure Atoll. A weight of 150 lb (68.2 kg) was considered ideal. An average weight of 156 lb (70.9 kg) was obtained for nine seals. Six seals are currently waiting departure.

Hematology and serum chemistry values for the 16 seals are being prepared for future publication.

All seals have been negative for canine distemper, Leptospira, Toxoplasma titers, and occult heartworms. Salmonella fecal cultures have been positive for 4 of the 16 seals. These were detected on four of the six incoming seals in 1991. All seals were clinically normal. Salmonella minnesota and S. havana were identified. The cultures were negative after treatment with antibiotics according to the sensitivity results.

Fecal samples for parasites were negative except for one seal that had tapeworms. Since most of the seals had not been feeding before arrival, the absence of worms was expected. The one exception was a late arrival (August) and was thought to have been feeding in the wild. This seal was also one of the fastest to take live fish, only 6 days after arrival. Treatment to eliminate tapeworms has been a problem. Standard canine dosages of 2.5 mg/lb of body weight of epsiprantel (Cestex) have not been successful.

Other veterinary problems include the following:

1.  conjunctivitis in one seal

2.  abscess in one seal with Clostridium isolated

3.  Streptococcus and Staphylococcus skin dermatitis in one seal

4.  infected shark bite wound in one seal, and

5.  a tail chewing syndrome seen in two seals.

All of these problems were resolved.

On occasion, monk seal pups must be sedated. Diazepam has proven to be a reliable and safe drug. Oral dosages of 0.8 mg/kg, IM dosages of 0.88-1.1 mg/kg, and IV dosages of 0.11 mg/kg have proven effective.

The rehabilitation program continues into 1992, with six seals waiting shipment in April or May. These seals will be "new stock" for Midway Islands, the area currently designated for replacement of rehabs into the wild population.

The Kure Atoll projects were deemed successful. Seals from the 1981 Head Start Project started giving birth in 1987, and the first rehabilitated seals began giving birth in 1991. The number of births in 1991 was 14, a significant change from the 1986 low and probably the highest number of births in the last 20 years. The beach counts of seals at Kure are now on the increase as well.

More importantly, the current population consists primarily of younger seals with a sex ratio favoring the females. With the departure of the USCG from Kure Atoll in 1992, the monk seal population is sure to flourish in this area.