The box measures 2.4 x 1.1 x 1.2 m high (96 X 42 X 48 in). 

 Construction is of 2 cm (3/4 in) plywood, thoroughly braced on the 

 outside. The box has vertically sliding doors in each end. The remov- 

 able top and false bottom are small enough to slide easily up and 

 down inside the box. The top has an overall oval dome shape 

 (roughly the shape of a prone male seal). Six persons can carry the 

 assembled box for short distances. 



Noise Makers 



Lightweight metal cans (2 to 5 gal fuel containers are appropriate) 

 with a few loose rocks inside, make effective noise makers that are 

 useful for driving large numbers of animals. These are shaken, or are 

 rolled along the ground behind moving animals. 



Marking 



Some kinds of research require repeated observations on the indi- 

 vidual animals within a season, or following known animals over 

 periods of several years. A few animals (particularly older males) 

 may be recognized repeatedly by characteristic scars or physical 

 abnormalities. However, positive identification from one field sea- 

 son to the next, or among different observers requires unequivocal 

 marking of individual animals. 



Tags 



Flipper tags have been the mainstay of the marking effort in the fur 

 seal program. Although we may apply more than one type of mark to 

 a given animal, the flipper tag serves as the ultimate identifier. Two 

 types of tags are currently in use, both originally designed as cattle 

 ear tags. 



Monel tags are U shaped plates of monel metal, which, when 

 closed, form a flattened oval ring through the animal's flipper. Once 

 applied the tags measure approximately 0.9 cm wide by 4 cm long 

 with numerals 0.6 cm high stamped into the metal. In good weather 

 conditions these tags can be read with binoculars at distances up to 3 

 or 4 m, or with high-powered spotting telescopes (45 to 60 x ) up to 

 35 or 40 m away. Monel tags cause mortality. Their use on pups has 

 been discontinued in favor of toe clipping (Johnson 1971). 



Because the portion of the tag that penetrates the flipper is a flat 

 blade (about 0.6 cm across), some injury may occur to the animals as 

 the tags rotate. (We have no confident assessments of adult mortality 

 which may be introduced by these tags, though we have seen many 

 adult animals wearing the tags without apparent adverse physical 

 effects.) Some improvement in the tag may be made by bending the 

 portion that penetrates the flipper into a round post. This modifica- 

 tion can be made with pliers, and the burred edges eased with a 

 motor-driven wire wheel. 



Jumbo Rototags are two-part plastic tags 1 .9 cm by 4.4 cm. They 

 come in various colors with 1.25 cm high black numerals heat- 

 stamped on both the upper and lower parts. These tags can be read by 

 eye at 3-5 m, and may be read up to 100 m away ( occasionally far- 

 ther) with spotting telescopes. 



One advantage of the Rototag is that the portion which penetrates 

 the flipper is a round post (about 0.5 cm in diameter) which allows 

 the tag to spin freely on its axis without enlarging the hole in the flip- 

 pen We do not yet have estimates of loss rate for Rototags in fur seals. 

 Some tags pull through the hole in the flipper, and a few tags break. 

 Tags applied 5 yr ago still have discernable numbers though some 

 more recently applied tags have faded. (Note: Rototags seem more 

 adequate for fur seals than for other otariids (Hobbs and Russell 

 1979).) The tags are applied to the posterior (trailing) edge of the 



front flipper, about 3 cm forward of the edge. There are two sites for 

 tag placement. One site is about 2 cm distal to the hairline across the 

 flipper. This site contains veins and nerve tissue, so tagging should be 

 done cautiously. In adult males the hairline site is too thick and 

 fibrous to penetrate with Rototags, so either a monel tag can be used, 

 or the animal can be tagged at the second site, between the 4th and 

 5th digits. The drawback of the latter site is that tags there are easily 

 torn out, especially in large males. 



Pelage Marks 



In addition to tags we generally apply a larger, more visible marie to 

 the pelage. Large (15-20 cm high) letter-number combinations may 

 be painted on the animals with bleach. We use a catalytic mixture nor- 

 mally available only to beauticians called "Lady Clairol Ultra-Blue." 

 This viscous liquid is painted on the dry or barely damp fur; and 

 rubbed in. Within 1 to 3 d the dark guard hair is marked with a pale 

 color ranging from a very bright beige to a fairly dark orange. If the 

 mixture is rubbed into the fur carefully, and the animal does not go 

 immediately into the water, the bleach can generally be expected to 

 "take," though our results have been varied; rarely does the process 

 fail to make a visible mark. A bleach mark considered "good" in one 

 year can usually be seen the following year, though it will generally 

 be faint and may not be readable. It is rare for bleach marks to last 

 more than one winter. This means that for an animal to be followed 

 for more than 1 yr (except by tags), it must be recaptured the follow- 

 ing season and be remarked. 



Maries may also be clipped in the guard hair with scissors. Clip- 

 ping away the dark guard hair reveals the lighter underfur beneath, 

 and leaves a readable mark without danger or injury to the animal. 

 We have no assessment of thermal stress caused by this mark. Clip- 

 ping marks is very slow work and the clipper's hands quickly tire. 

 Clipped marks last perfectly well through one breeding season, but 

 cannot be seen the following season. Maries clipped in the fur of pups 

 early in the season will probably be completely grown in by mid- to 

 late-October. 



Two types of paint have been used with some success. Quick- 

 drying highway or traffic paint adheres to the guard hair reasonably 

 well, and if the animal does not go immediately into the water, the 

 paint may stick for 2 to 3 wk. We use this paint to temporarily mark 

 animals which we intend to capture and mark permanently at some 

 later date. The paint can be applied with a sponge attached to the end 

 of a bamboo pole. Identification by this method involves memorizing 

 the irregular splotch marks of paint, or drawing sketches of the pat- 

 terns on history cards for individual animals. The history cards 

 should by updated frequently, since the paint gradually flecks off, and 

 the size, shape, and pattern of the marks change with time. 



Workers under contract to the National Marine Mammal Labora- 

 tory used a plastic resin naphtha-based paint marketed by Lenmar, 

 Inc., which provided long-lasting (6 to 8 wk) marks in the pelage of 

 fur seals (Griben 1979). Later examination of pelts from animals 

 taken in the commercial harvest on St. Paul Island revealed abnor- 

 malities in both the guard hair and the underfur where paint was 

 applied. We do not recommend the use of this naphtha-based paint on 

 fur-bearing animals until more work is done to determine potential 

 damaging effects. 



We believe that branding with a hot iron is, on balance, the most 

 humane way to mark seals permanently with a large mark suitable for 

 behavioral research. It is preferable to slightly injure an animal once 

 in its life by branding than to recapture it every year to refresh tempo- 

 rary marks, such as bleach or hair clipping provide. When executed 

 carefully, skin-branding provides a good mark without serious injury. 

 We have followed skin brands on some seals for 5 yn 



