Overgrown hooves from muskoxen (Ovibos moschatus) of Kangaarsuk (Kap Atholl) Northwest Greenland. Technical Report No. 41

Technical report no. 41, 2002 Greenland Institute of Natural Resources Overgrown Hooves from Muskoxen (Ovibos moschatus) of Kangaarsuk (Kap Atholl) Northwest Greenland Title: Overgrown hooves from muskoxen (Ovibos moschatus) of Kangaarsuk (Kap Atholl) Northwest Greenland Authors: Christine Cuyler & Hans S. Mølgaard Translation: Sofia Geisler Funding: Greenland Home Rule, Department of Environment and Nature Series: Technical Report Publisher: Greenland Institute of Natural Resources Cover photo: Fore leg hoof of a 13 year old female muskox from Kap Atholl, Northwest Greenland. Photo: Christine Cuyler ISBN: 87-90024-97-4 ISSN: 1397-3657 Layout & Printing: Oddi Printing Ltd. Number printed: 100 Reference: Cuyler, C. & Mølgaard, H.S. 2002. Overgrown hooves from muskoxen (Ovibos moschatus) of Kangaarsuk (Kap Atholl) Northwest Greenland. Greenland Institute of Natural Resources. Technical report no. 41. 28 pp. Available from: Greenland Institute of Natural Resources P.O. Box 570 DK-3900 Nuuk Greenland Phone: +299 32 10 95 Fax: +299 32 59 57 www.natur.gl Overgrown Hooves from Muskoxen (Ovibos moschatus) of Kangaarsuk (Kap Atholl) Northwest Greenland by Christine Cuyler1& Hans S. Mølgaard2 1Greenland Institute of Natural Resources, P.O. Box 570, DK-3900 Nuuk, Greenland 2Hunting & Fishings Consultant, Aqqusinersuaq 8, DK-3911 Sisimiut, Greenland 3 Technical report no. 41, 2002 Greenland Institute of Natural Resources Contents Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Eqikkaaneq . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Sammenfatning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Literature Cited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Appendix 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Appendix 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Appendix 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Appendix 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Appendix 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Appendix 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Appendix 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 4 Summary In 1986, 7 muskoxen (5 females, 2 males) were introduced to Kangaarsuk/Kap Atholl (76°19’ N, 69°22’ W), Qaanaaq municipality, Northwest Greenland. Hunting has never been allowed. This 1998 study focused primarily on the overgrown hooves of muskoxen at Kap Atholl. Also noted or studied were fat reserves, horn growth, mandible measurements and tooth wear. 14 Kap Atholl muskoxen were collected on 16 & 17 April 1998; 6 adults, 7 sub-adults and 1 yearling. One female was 13 years old; being one of the original animals introduced to Kap Atholl. Hooves on all adults were severely overgrown, e.g., fore hooves 25 to 49 cm long. Hooves on sub-adults were longer than expected, e.g., fore hooves 15 to 27 cm long. Normal adult and sub-adult fore leg hoof length is 16.1 ±2.0 cm (n = 32). Severely overgrown hooves on the 4 adult bulls did not appear to impede locomotion on the hard surfaced snow. Veterinary examination of animals did not reveal any pathogenic cause for the deformed hooves. Kap Atholl muskoxen have large body size, excellent teeth and good body condition. They also have dry flaky horns. What causes the deformed overgrown hooves has not been shown, nor any reason for the dry flaky horns. The overgrown hooves and dry flaky horns are likely the result of a common cause. The responsible factor(s) remains to be identified, candidates include, 1) high concentrations of a nutrient in the vegetation, 2) lack of locomotion and abrasion, and 3) a possible genetic inbreeding defect. Eqikkaaneq Umimmaat arfineq-marluk (kulavaat tallimat tiggaallu marluk) Qaanaap Kommuneani Kangaarsummut (76°19’ N, 69°22’ W) 1986-mi nuunneqarput amerliartornissaallu siunertaralugu eqqissisimatitaallutik. Umimmaat taakku qanoq innerat Avatangiisinut Pinngortitamullu Pisortaqarfiup Pinngortitaleriffiullu suleqatigiinnerisigut 1998-mi misissorneqalerpoq. Tunuliaqutaasoq tassaavoq umimmaat tamaangaaneersut kukiffaasa naliginnaasumit anginerulerlutik iloqissersimasut naammattoorneqartalersut misissuiffiginissaat. Misissuinermi aallaavigineqartut taakkuupput iluatsilluguli ilanngullugu misissorneqarput tunnoqassusiinut, nassuinut, qarngannut kingutaannullu tunngasut. 1998-mi aprilip qiteqqunnerani Kangaarsummi umimmaat 14-it pisarineqarput tassalu inersimasut arfinillit, inuusukaat arfineq-marluk norrarlu ataaseq. Pisarineqartut ilagaat kulavak ukiunik 13-nik utoqqaatigisoq 1986-mi nuunneqartut ilaat. Inersimasuni tamani kukiffaat isikkumikkut allanngorsimanerat malunnarluarpoq. Assersuutigalugu siulliivini kukiffaat 25-49 cm-terisut angitigaat. Angutivissat arnavissallu inuusunnerusut kukiffaat ilimagisamit takinerupput 15-27 cm-terisut takitigigamik. Umimmaat siulliivini kukiffaat takissusaat – inersimasuni inuusunnerusunilu – naliginnaasoq tassaagajuppoq 16,1 +/- 2,0 cm (n=32). Tigganni sisamani kukiffaat allanngungaatsiarsimanerat apummi manngersumi pangalinnissaannut akornutaarpasinngilaq. Uumasut nakorsaata misissuinerata takutippaa kukiffaat isikkumikkut allanngorsimanerat nappaammik pissuteqarani allamik patsiseqarsimassasoq. 5 6 Kangaarsummiittut umimmaat timaat naliginnaasumit anginerupput kingutaat nungullarpiarsimanatik tunnoqarluarlutillu. Tiggaat kulavaallu ilarpaaluisa nassui qulloorsimapput panernerannik nassuiaatissaqarunartumik. Kukiffaasa allanngorsimanerannut nassuisalu qulloorsimanerannut pissutaasinnaasut misissornissaat periarfissaqarsimanngilaq, patsisaasorli ataasiugunarpoq. Sunniuteqarsimasinnaasut misissugassat makkuusinnaapput 1) nerisaasa akuisa ilaasa tiggaat kulavaallu nassuinik kukiffaannillu sunniisinnaasut annertusisimanerat 2) uumasut nikippiartannginnerisa kukiffaannik nungullartitsisarnerat, 3) uumasut avataaneersunik akuneqartannginnerisa kinguneranik innarluutinngorsimasinnaanera. Sammenfatning I 1986 blev 7 moskusokser (5 køer og 2 tyre) udsat ved Kangaarsuk/Kap Atholl (76°19’ N, 69°22’ W) i Qaanaaq kommune, Nordvestgrønland. Okserne blev fredet for at muliggøre vækst i bestanden. I 1998 gik Direktoratet for Miljø og Natur og Grønlands Naturinstitut sammen om en undersøgelse af bestanden. Baggrunden var de forvoksede klove, som blev observeret hos moskusokser fra dette område. I undersøgelsen blev der derfor også hovedsageligt fokuseret på oksernes forvoksede klove, men oksernes fedtreserver, hornvækst, kæbemål og tandslidtage blev også undersøgt. Medio april 1998 blev 14 moskusokser nedlagt ved Kap Atholl; 6 voksne dyr, 7 ungdyr og 1 årskalv. En af køerne var 13 år gammel og er en af de “oprindelige” okser, som blev udsat i 1986. Klovene på alle de voksne dyr var meget forvoksede - eksempelvis var klovene på forbenene 25-49 cm lange. Klovene på ungdyrene var længere end forventet - de var 15-27 cm lange. Den normale længde for klove på forben af moskusokser er 16,1 ±2,0 cm (n = 32) for både voksne og unge dyr. De meget forvoksede klove på de 4 voksne tyre forhindrede tilsyneladende ikke dyrene i at løbe på det hårde snedække. Dyrlægens undersøgelser viste, at de misdannede klove må skyldes andre årsager end sygdom. Moskusokserne ved Kap Atholl havde relativt stor kropsstørrelse, meget lidt tandslidtage og gode fedtreserver. Desuden var hornene flækket på en del af okserne, hvilket formentlig skyldes udtørrede horn. Det har ikke været muligt i denne undersøgelse at afdække årsagen(erne) til de misdannede klove og de flækkede horn. Årsagen er muligvis den samme. De mulige ansvarlige faktor(er), som kunne undersøges videre, inkluderer, 1) forhøjede koncentrationer af stoffer i vegetationen, der påvirker vækst af horn og klove hos okserne, 2) manglende bevægelse og dermed nedslidning af klove, og 3) en genetisk indavlet defekt. Introduction Muskoxen (Ovibos moschatus) may once have been indigenous to Kangaarsuk /Kap Atholl in the Qaanaaq region of Northwest Greenland. Extremely old muskox craniums, bones and horns have been found in the area (Burnham pers. comm.). In the late 20th Century, however, muskoxen were not present. On July 11th 1986 a total of 7 year7 Figure 1. Map of the study area indicating where 14 muskoxen were sampled in 1998. ling muskoxen (2 males and 5 females) were taken from the Kangerlussuaq area and introduced to Kap Atholl. Since their release the muskoxen have been protected by law. By 1990 all of the muskox resided in the Maniisergat Valley, which is also called “Den Grønne Dal” (The Green Valley) (Figure 1). The valley is named for its lush vegetation, which results from the many large colonies of Little Auk (Alle alle) found there. During summer, muskoxen are usually found in the dense grassy areas under the bird colonies. The vegetation there is lawn-like with a deep layer of peat below and few stones to cause chipping or wear on hooves (Burnham 1996). Calving was first reported in 1991, when a group of 7 muskox including 2 calves was seen (Peter Nielsen pers. comm.). Muskoxen were again observed in spring 1993. This time 6 animals, which included calves, were seen deep in the Narsaarsuk Valley (Ole Mathiesen pers. comm.). The Peregrine Fund, working in the Kap Atholl region during July 1994, observed 1 lone bull and a herd of 19 muskoxen, which included 7 calves (Burnham 1996). This sighting was confirmed in August of the same year during an aerial survey completed by the Directorate for Health and Environment (Peter Nielsen pers. comm.). The next year, 1995, 2 lone bulls and a herd of 24 muskoxen, which included 7 calves were seen (Burnham 1996). In the summer of 1996 a herd of 33 muskoxen, which included 8 calves, were sighted in the Maniisergat Valley, and severely overgrown hooves, grown up and around 360°, were noted on many adults (Burnham 1996). The worst affected animals had difficulty walking. Veterinarian Niels Wøldiche Pedersen investigated the situation in November 1996 (unpublished data). He located a herd of about 30 muskoxen, of which 5 to 10 of the oldest animals had difficulty walking. They had severely overgrown hooves, which looked similar to corkscrews and caused abnormal leg position. One of the adult bulls was collected. All 4 hooves were overgrown, with the foreleg hooves being worst and longest, e.g., the corkscrew-like front hooves measured 50 cm and 44 cm. Body condition was considered below average, however, no pathological changes were found in the digestive system. By July of 1997 the original single herd had split in two and as before there were some lone bulls (Burnham pers. comm.). The total was 47 muskoxen, which included 12 calves, and between 7 to 12 adults had severe hoof problems (Burnham pers. comm.). Muskoxen with overgrown hooves could be found in both the Narsaarsuk and Maniisergat Valleys of the Kap Atholl region (Anette Grøngaard pers. comm.). Adult muskoxen within this introduced population of the Kangaarsuk/Kap Atholl area of Northwest Greenland had been observed to possess long curled hooves. Local opinion held that the overgrown hooves caused suffering, we therefore investigated the problem by collecting overgrown hooves in the Kap Atholl area of Northwest Greenland in April 1998. This report presents the findings from that study. Several comparisons are made to measurements typical of normal adult muskox of the founding Kangerlussuaq stock. 8 Methods During spring 1998, 14 muskoxen were shot at Kangaarsuk/Kap Atholl in Northwest Greenland (76°19’ N, 69°22’ W) (Figure 1). Hunters from the town of Qaanaaq were responsible for the collection, and were accompanied by wildlife officers Hans Mølgaard (Sisimiut Municipality) and Jacob Heilmann (Maniitsoq Municipality). Transport was by dog sled. General observations about the Kap Atholl terrain surface and vegetation were made. Although instructed to shoot 15 adults, all muskoxen seen were shot regardless of age. An entire herd of 10 animals was collected deep inside the Maniisergat Valley (76°20’ N, 68°52’ W) on April 16th. The next day, April 17th, a group of 4 bulls was collected further south inside a small un-named valley (76°16.5’ N, 68°54’ W). The mandibles from 13 animals and the hooves from 14 animals were sent to the Greenland Institute of Natural Resources for examination and measurement. Samples of mandible and hooves of each animal were kept together and were labelled after arrival at the institute. All mandible and hoof samples were then given tags indicating region (KPA), collection year (98), and an animal number (1 to 14), e.g., KPA98-1,-2,-3,…-14. All hooves were photographed (Appendix 4). Hoof length measurements were taken along the distal border of the abaxial wall, starting at the coronet (transition line between skin and hoof) and ending at the toe of the hoof (Figure 2). The maximum hoof length for each foot was the measurement chosen. Since the hooves on the oldest animals curled onto themselves extensively, the length of the hoof sole was not taken. All mandible, diastema and tooth wear measurements were taken on the left mandible, buccal side (unless otherwise specified). Tooth crown height on first incisor (I1) and the anterior crest of the first molar (M1) were measured for tooth wear. Mandible length was used to indicate the sex of the muskoxen collected, the males being longer. Age was indicated by tooth eruption (Carsten Riis Olesen unpublished). Since muskoxen typically are born during May and all animals were collected in April, an animal of almost 4 years would be put in the 3 to 4 year old age class. An animal of almost 3 years would be put into the 2 to 3 year old age class, etc. Those with a full set of adult teeth were placed in the > 4 years old age class. Cementum rings from the interior of the second and third molar (Mads C. Forchhammer unpublished) were used to age the Kangerlussuaq female, whose incisors and molar tooth row are shown in the results. Overgrown hooves from two Kap Atholl adults were sent for further analysis to the Laboratory of Veterinary Pathology, Royal Veterinary and Agricultural College, Institute of Pharmacology and Pathology, Denmark. At this laboratory the hooves were x-rayed and examined anatomically. For the purposes of comparison, hoof length measurements and jawbones were collected from muskoxen in the Kangerlussuaq area of West Greenland (ca. 67°N; 51°W), where overgrown hooves are not a problem. Hoof measurements were obtained from 13 and jawbones from 17 muskoxen during the Kangerlussuaq winter hunt February 2001. The Kangerlussuaq sample was opportunistic and included 4 adults, 4 sub-adults and one calf (Table 3). The student t-Test, assuming unequal variance with two-tailed 9 Despite the above speculations into various theories, the cause of the overgrown hooves among the muskoxen at Kap Atholl is still unknown. Further investigations to ascertain possible inbreeding could include: 1) locating and examining the original introduced (eartagged) individuals still alive to learn if the problem is constant; and 2) locate and examine all family groups at Kap Atholl to verify whether all or only select family groups are affected. Finally if pasture is the cause, determining whether the geographically distinct Kap Atholl area is the only region the problem appears in could clarify the issue. Hence the possible presence of overgrown hooves in other regions should be checked. Acknowledgements Asincere thank you to the 6 Qaanaaq hunters and 4 dogsled drivers. They achieved the Kap Atholl collection, despite storms and other obstacles. The Greenland Directorate for Environment & Nature funded and organized the collection. The Greenland Directorate for Industry provided the wildlife officers and hunter contacts. Dr. Henrik Elvang Jensen did the pathology work. Thanks to Sofie Ruth Jeremiassen and Linda Odgaard in lab work, Casper Christoffersen for scanning photos, Pipaluk Møller Lund for map figure, Bjarne Lyberth for Kangerlussuaq data, and Kirsten Nielsen, Erik Born & Arild Landa for reviewing the manuscript. 16 Literature cited Burnham, W. 1996. Progress Report 1996: Thule Greenland Project. The Peregrine Fund, 566 W. Flying Hawk Lane, Boise, Idaho 83709, USA. 10 pp. Pasquini, C. 1982. Atlas of bovine anatomy. Sudz publishing, 1222 S. Hwy. 377. Pilot Point, TX, 76258. 335 pp. Skogland, T. 1988. Bestandsdeynamisk analyse av villreinstammen i Forelhogna: III Effekten av tannslitasje på livshistorie. Villreinen. pages 20-22. (in Norwegian) Skogland, T. 1994. Villrein, fra urinnvåner til miljøbarometer. Teknologisk Forlag. 143 pp. (in Norwegian) Vibe, C. 1981. Landpattedyr: moskusoksen. - In: A. Nørrevang and J. Lundø (eds.), Grønlands natur. Politikens Forlag. Pages 479-482. (in Danish) Vibe, C. 1986. Tilbage til de gamle græsgange. Augut. Pages 6-7. (in Danish) 17 Appendix 1. Raw data for measurements of hoof1lengths, muskoxen, Kap Atholl, spring 1998. Muskox ID Age Age (years) Sex Foreleg hooves (cm) Hind-leg hooves (cm) KPA98-1 adult > 4 male 30 49 22 21.5 KPA98-2 sub-adult 1 to 2 female 16 15 14 13.5 KPA98-3 sub-adult 1 to 2 male 17 20 15 14 KPA98-4 adult >4 male 30.5 30.5 20 20.5 KPA98-5 adult > 4 (13 yr) female 35 35.5 19.5 20 KPA98-6 sub-adult 3 to 4 male 27 26 21 20.5 KPA98-7 sub-adult 2 to 3 female 18.5 18 13 15 KPA98-8 sub-adult 1 to 2 female 18 19 15 13.5 KPA98-9 adult > 4 female 38 31 17 18.5 KPA98-10 sub-adult 2 to 3 female 23 26 18.5 20 KPA98-11 yearling < 1 unknown 15.5 15 12 12.2 KPA98-12* adult > 4 male 24.5 25 25 28.5 KPA98-13 adult > 4 female 32.5 35 30 31 KPA98-14 sub-adult 1 to 2 female 20 19.5 17.5 17 * mandibles unavailable, therefore age and sex deduced from field report and hoof measurements. 1although there are two “toes” per hoof, only the maximum length for each hoof was recorded. Appendix 2. Raw data measurements of maximum mandible & diastema lengths, left buccal side, muskoxen, Kap Atholl, spring 1998. Muskox ID Age Age (years) Sex Diastema (cm) Mandible (cm) KPA98-1 adult > 4 male 12.0 40.5 KPA98-2 sub-adult 1 to 2 female 9.0 29.9 KPA98-3 sub-adult 1 to 2 male 10.1 31.4 KPA98-4 adult > 4 male 11.2 40.0 KPA98-5 adult > 4 (13 yr) female 10.4 36.7 KPA98-6 sub-adult 3 to 4 male 11.6 38.0 KPA98-7 sub-adult 2 to 3 female 9.4 32.1 KPA98-8 sub-adult 1 to 2 female 8.8 30.0 KPA98-9 adult > 4 female 10.4 37.0 KPA98-10 sub-adult 2 to 3 female 9.1 Broken KPA98-11 yearling < 1 unknown 7.6 25.5 KPA98-12* adult > 4 male – – KPA98-13 adult > 4 female 10.4 36.0 KPA98-14 sub-adult 1 to 2 female 9.1 30.3 *mandibles unavailable, therefore age and sex deduced from field report and hoof measurements. 18 Appendix 3. Minimal tooth wear: Raw data measurements, left buccal side, muskoxen, Kap Atholl, spring 1998. Muskox ID Age Age (years) Sex I1max tooth I1max tooth M1max tooth crown height above crown height, anterior gums (mm) height (mm) crest (mm) KPA98-1 adult > 4 male 11.8 12.0 17.7 KPA98-2 sub-adult 1 to 2 female 7.7 15.7 17.3 KPA98-3 sub-adult 1 to 2 male 11.3 14.4 17.1 KPA98-4 adult > 4 male 12.5 13.8 18.6 KPA98-5 adult > 4 (13 yr) female –110.0121.72 KPA98-6 sub-adult 3 to 4 male 11.4 13.7 17.4 KPA98-7 sub-adult 2 to 3 female 12.5 13.7 17.8 KPA98-8 sub-adult 1 to 2 female 10.3 15.1 17.9 KPA98-9 adult > 4 female –19.5119.32 KPA98-10 sub-adult 2 to 3 female 11.2 12.3 18.9 (right side) KPA98-11 yearling < 1 unknown 6.2 3.9 14.8 KPA98-12* adult > 4 male – – – KPA98-13 adult > 4 female –19.4122.12 KPA98-14 sub-adult 1 to 2 female 12.3 14.9 18.4 * mandibles unavailable, therefore category, age and sex deduced from field report and hoof measurements. 1Although tooth crown still of substantial height the enamel on tooth’s buccal surface is worn away. 2Increased tooth crown height was the result of jawbone erosion, which revealed more of the tooth crown. Hence the oldest animals had the greatest tooth crown heights. No roots were ever visible on molars. 19 20 Muskox KPA98-1; age > 4 years. Muskox KPA98-2; age 1 year 11 months. Muskox KPA98-3; age 1 year 11 months. Muskox KPA98-4; age > 4 years. Muskox KPA98-5; age > 13 years. Appendix 4. Photos of overgrown hooves, Kap Atholl muskoxen, April 1998. Shown are a lateral view of a fore-leg hoof, followed by ventral views of foreleg and hind-leg hooves, unless otherwise indicated. (Photos C. Cuyler) 21 Muskox KPA98-6; age > 3 years 11 months. (dorsal views 2 forelegs & ventral view hind-leg hooves shown). Muskox KPA98-7; age > 2 years 11 months. Muskox KPA98-8; age > 1 year 11 months. Muskox KPA98-9; age > 4 years. Muskox KPA98-10; age 2 years 11 months. 22 Muskox KPA98-11; age > 11 months (yearling). (dorsal & ventral view forelaeg, ventral view hind-leg hooves). Muskox KPA98-12; age > 4 years. (dorsal view forelaeg, ventral view forelegs, ventral view hind-leg hooves). Muskox KPA98-13; age > 4 years. Muskox KPA98-14; age 1 year 11 months. 23 Age > 4 years. 1 year 11 months. 1 year 11 months. Age > 4 years. Age > 4 years (13yr). 3 years 11 months. 2 years 11 months. 1 year 11 months. Age > 4 years. 2 years 11 months. 11 months. Age > 4 years. 1 year 11 months. Appendix 5. Photos of incisor teeth, Kap Atholl muskoxen, April 1998. Note the extensive remaining tooth crown and minimal tooth wear on adults KPA98-1,-4,-5 (13yr),-9 & -13. (Photos C. Cuyler). 24 Age > 4 years. 1 year 11 months. Appendix 6. Photos of left molar tooth row, Kap Atholl muskoxen, April 1998. Note minimal tooth wear on occlussal surfaces of adults KPA98-1,-4,-5 (13yr), -9 & -13. (KPA98-10 right molar tooth row illustrated as left mandible was shot.) (Photos C. Cuyler). 1 year 11 months. Age > 4 years. Age > 4 years (13yr). 3 years 11 months. 2 years 11 months. 1 year 11 months. Age > 4 years. 2 years 11 months (right side). 25 11 months (yearling). Age > 4 years. 1 year 11 months.