ANNUAL MEETING - JUNE 1967 Catch of Harp Seal, Hooded Seal, and Bearded Seal at West Greenland Museum, Copenhagen

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1 NTERNATONAL COMMSSON FOR RESTRCTED THE NORTHWEST A nannc FSHERES Serial No. 92 (D. c. ll) CNAF Res. Doc. 67/2 (Seal Contribution No.3) ANNUAL MEETNG - JUNE 967 Catch of Harp Seal Hooded Seal and Bearded Seal at West Greenland EV: Chr. Vibe Zoological nstitution and Museum Copenhagen Dr. Paul Hansen has rec'uested the writer to give a short 'summary of his view of the heavy fluctuations in the occurrence of Harp Seal Hooded'Seal and Bearded Seal in West Greenland ar..d to draw a comparison to the fluctuations at Newfoundland. The writer has not Ulortunately had the 0 pportuni ty to discuss the material with experts and would therefore welcome any comments which the Norwegians and Canadians may wish to add. At the top of fie. is sllo'lm slo'lln a curve of the average drift-ice advance in Davis Strait for the months of May and August (A) i. e. the early and the late drift-ice and (B) shows the Stm spot curve. t allpears that each sun spot maximum generally correlates with a drift-ice minimth~. The heaviest drift-ice advances occur during the periods between the sun spot maxima. Each approximately - year urift-ice period is a~ain divided into two or three smaller ice advances i.e. one half or one third of the sun spot period respectively. Eost Greenlandic animal populations display much the same fluctuations (with averagely 3-4 or 5-6 years betvleen the maxima) n the middle of fig. is shovm a curve of the average drift-ice advance in Davis Strait for the months of May June July and August (in 3-year sliding averages). This curve falls in three sta"es stao;es i.e. a st8;':2.tion st2;':2.tion stage (0) a pulsation sta";e (D) and a meltin~ stage (E). After 960 the latter appears to be succeded by another sta~nation stage. The existence of these drift-ice stages can be demonstrated centu.ries back in tine when they determined the size of the populations of land and sea mammals in and off West Greenland (and in the whole Atlantic-Arctic area). During the entire stal':nation sta!;nation stage the drift-ice does not advance far in Davis Strait but then the Baffin Bay ice sprcads far southeast. The Southwest Greenland climate becomes-dry becomes dry.arctic OO:'~inental. The :i.eindeer population of West Greenland strongly increases and the ~ider breeding fields are concentrated at South- "lest Greenlcnd. The greatest occurrence of Harp Seal is in lisko F2 /2 t.t

2 -2'- ~ Bugt a~d farther south; the capacity of the production field is highest when it is situated here. Both at West Greenl:mdand Greenl::mdand at Newfoundland the Harp Seal is extremely numerous as is seen from the curves cur~es F and which include the catch of Hooded Seal S~al (in West Greenland Bearded Seal and Harbor Seal too; both ;ze a.re few in number). Probably- the Hooded Seal too occurs sparsely at West Greenland during the stagnation stage. n West Greenland the catch of Harp Seal follows the rhythm of the sun spot curve (80-860). During the succeeding drift-ice ' stages when Davis Strait experiences an Atlantic'clim:;tte the rhythm of the catch of Harp Seal at West Greenland is the opposite of that of the sun spot curve (with the exception of the period before 90 and that after 90 which coincide with the transition from driftice stage D to drift-ice stage E when the amount of drift-ice is the same as during stage C). During the pulsation stage (D) the catch of Harp Seal decreases strongly at West Greenland (curve G which only comprises Harp Seal) The Harp Seal becomes less numerous at Southwest Greenland but then the population increases farther north in the Umanak Fiord. The reason seems to be the cold East Greenland Arctic water advancing into Davis Strait. After 900 the number of Harp Seal goes up again in Disko Bugt. The reason seems to be that the advance of the cold East Greenland Arctic water into Davis Strait moderates'again. After'920 and 930 the catches increase further and the Harp Seal shows up at Uernavik and Thule too. After that time the catch has remained fairly large in West Greenland until 950. During the period it Vias reduced to half from about to about (curve H shows the total catch according to the hunting statistics). A natural increase during the sun spot minimum around 960was to ~o be exp~cted but failed. Hence the Cluestion arises whether the decrease in the 'catch 'of Harp Seal at Greenland may be caused by the large catches at l(ewfoundland during the years of and 964. ""' ' 'Pig. 'bo'tto'mcu:tvj'''s:hbvis<'th!i' 'bo'tto'mc"u:tvj'''s:hbvis<'th!i' (\ai!ch'~s ''B't''N!!Wfchfud:J:ahd 'lili'cording to Thor versen 927 p. 8 () from sail ships ruld steamers (J) from steamers. t appears that years with great catches at newfoundland are followed by years with small catches at Greenlana. However it cannot be safely concluded that the decrease in the Greenland catches is due to the increase in the Ne\'lfoU}(lund catches; it is poseible that' the Harp Seal stays away from Greenland under certain drift-ice conditions. F3.... /3

3 - 3 - The exceptional increase in the total catch at Greenland just after 940 may be due to the discontinued catch at Newfoundland dur.ing the war but on the other hand :the increase correlates with the ~atural rhythm in relation to the sun spot curve' and may consequently ;just as well have a natural cause.!fowever fig. 3 seems to demonstrate demonstrate a close correlation between the size of the catch at Newfoundland and its deci'ease and and increase at Greenland. These curves show the actual number of Hooded Seals and Harp Seals caught. The catch at Greenland during te the period st April 952-3st March 953 is registered under 952 and so forth i. e. the year when the pups were caught at Nevltoundland. < With a catch of about Harp Seals at Newfoundland the Greenianders' Greenlanders' catch may reach about but if the former rises to about the latter is reduced to half. The falling tr~' at Greenland from may indicate that the whole population is over-exploited. Fig. 2 top shows a curve of the year temperature at Upernavik. The low temperatures until 925 seem to be a direct consequence of the great drift-ice masses in Davis Strait during the pulsation. t stage (bottom curve). After 925 the year temperature is at a higher level. The curve of the August drift-ice advmces demonstrates' that eaoh drift-ice advance is reflected in a temperature fall at Upernavik. The curve of the purchase of Bearded Seal skins' at Julianehab (the domestio oonsumption is not included) shows that the catch is greatest when the drift-ice is at minimum. This is true also of the oatoh of Hooded Seal (purchase of skins in the whole of West Greenland from Julianehab to Upernavik). "A A oomparison between the Hooded Seal curve and bottom drift-ice curve (the latter in 3l-year sliding averages) may sugge~t that the Hooded Seal visited Davis strait preferably during the-drift-ice pulsation stage (860-90). The population began declining at West Greenland simultaneously with the decrease.in in the Davis Strait drift-ice. After 90 the Hoodedsea..sea... thus;:.seems. to p;r;:e.fer p;r;'.e.fer :t;ee.dinggr.ounds fee.dinggr.ounds outside Vlest Greenland. The writer v~iter has not had opportunity to compare the Greenland Hooded Seal catch to the catch elsewhere. Copenhagen ljay 24th /4 F4

4 - 4 - "-" West Greenland Upernavik-Julianehab... " Ho"oded Ho oded Seal (H~ting - statistic) Harp Seal (Hunting'" (Hunting' statistic)? 952 Q...08) (/ /3 953) 952 (8.526) 3 (.58) 3 (8~726) Scoresbysund Angmagssalik Hooded Seal Harp Seal Hooded Seal Harp Seal 954/ Y x " }4 "} " y) 44 by KGH x) 773 by KGH. 32 by Greenlanders 327 by Greenanders... /s FS

5 - 5 - '/ - r" '.'--:0--;--"--'--"'-'-- '.'--; r-----;--. ' East GrctOnlAnd GrctonlAnd e" advanco N. W of Kop Farvol in mil (May+Augu5l): : (3.y (3 y r lliding averages): A '50 Milo!) 265 Number of sun-spots B 80 BO 20 No. 80 East Greenland ce (May +Juna +July +August) (3 year sliding averages) ~.~--~-C--~-- +-~~---+D----~ BOoo "' F ' C f r : D '\ \{ "\ Harp Seal and : 'v : \ Hooded Seal W. Greenland Hooded Seal W. Greenland : ' (a-year sliding averages) SOl r : '\ A J\ r\ ~ ~' i J \r V\ r\f:\ ~\f\ r' "\ Harp Seal and Hooded Seal Newfoundland (after Th.lven.n 927).av: Vibe ' year Sliding slidi!'lq averages') av~rages:) ' BO ~ Harp Seal W. Greenland 3-year a-year sliding avlragas averagas : :J : '" '0.0 'ODD &000 " D ~ BOOD BOOC No seals caught ti~ seals purchased Fig. ~ +> (' -' "'. i:"o /6 F6

6 .. - ( ' c''----; - - 5{~ ; -6 Air temperatures Upernavik April st to March 3 (3'year sliding averages) Miles The E<:~t Greenland ce advance NW. of Kap Farllel in August (3-year (3-)9ar stiding averages) ~~ lou!0~ Furs of BpBrded Seal purchnsed at 'i!) p"" ''''0' " " ~_ Juliafl'lhAb. ".. t~~ (3y sliding ""'''''''' \A~" t if' U <; 'Jf Hnndp." ~~'d' A 'y pl" ch"ed f!. W";! d C ' r u ' chilsed (Julirlngh~b if! W";! GrroQnland rp~nland VA (Julirlngh~b. to U" UpNrw'ik) ~r. 3-year slid. -' k) ' (3-year( sliding 09 averages) : t The East Greenland ce advance N N.W. of Kap Farvel May to Augu!';t (3-years (3-y~ars slidil''j i:l'oerages) ' "" '.'''''<. ' ;.. \~ \JV(v/'v \r' : ~:! n 00 f:\ 0 J r ')\ "}. '\..)A.f/'v : No ~L Chr. C~.~~~_ V.~~~_L L.-.l. L_L_ J L.!) \ 80 ' : 60 7if-- 70 DO Fig. 2 /7 F7

7 f Hooded Seal SeaL West Greenland... z ::To o C -. lfl;:) OJ ;:). Cl. V Harp SepL West GreenLand '_..' J..-L...J...L-L.J...L-.l...J...L..J...J'-'-..L-' _ Ch r: Vi bf> Harp Seal Newfoundland NewfoundLand Gulf + Front (Sergeant Fig. 3 Fa