Document jmEVvbEz5e8ka4vzXv6qXp4d9

w.'B. 9/) t\ x oQE - St, L 0 UlS Seal Deaths in Cornwall Autumn 1969 DSM 026799 STLCOPCB4010761 U .) Poro-ifi-rd Tho ocourronce of deaths amongst seal pups in Cornwall in tho autumn of 1969 was investigated by tho Sci&lo Lenoarch Unit of H 3-ll-C. Tiki Officer in Charge of the Coals Research Unit gave interviowc to the preen and ir.for;vj thorn of tho progruou of these investigations, how that thv3e arc co;npleto, we thought it would bo in tho best interests of everyone if an cxtencive account worn produced. Thu following report in not in the strict forin of a scientific paper and is somewhat more diocuruivo; it is hoped that those receiving it will bear this in mind. Nevertheless, the inventigations reported and the con clusions reached have been pursued with the utmoct scientific rigour. AckrowIedgomo pie Tho Neural Environment Hesearoh Council (N E R C.) and the Seals Reuonroh Unit are muoh indebted for the help they received from people mentioned in the report, arid in particular, for the co-operation they received from Mr. Jones, who runs a seal Bimctuary at'St. Agnes in Cornwall, and the Royal Society for the Prevention of Cruelty to Animals (R S P C A ). Tho facilitio:: aoooruod by tho Ministry of Agriculture, Fisheries and Food (]' A V F ) locally' were of great assistance and wo are particularly indebted to Mr. A.V. Holden of tho Department of Agriculture and Fisheries for Scotland Fisheries Labor.-.:tory at Pitlochry, arid to Mi". S.fi. Allen of the Nature Connervancy*b Mcrlewood Rcoonrch Station for the chemioal analyses. DSW 026800 STLCOPCB4010762 f 1. )( .) ImUm'I ' j cn Considerable publio ooncern wan exprennnd in the autumn of 1969 ful low ing reports of dead and dying peals being wunhod up on Cornwall uhoroc. Tito reports referred mainly to .young soalB but also to adult unalu suffering frotu Ion ions which were dtwmribod au "burn marks". Those re ports followed clonoly on the reported deaths of around ten thousand guillemots arid other birdu of the mik family in tlto region of tlie Northern Irish Goa iri Oeplninlx'i- and .Out a bur, Homo of 11 in no b.trdc worn found on examination to have higher levclu (>f now orgunochlorine compounds in their livers than ore normally detected in routine iiioui loving, and thin load to suggestions that tho Deal deatliH might be nimilr arly oonnocted wltli pollution, 1. Tho NGHC Seals Ueuearoh Unit investigated tho event with tho help of T various other organisations and people, Most reports of Renin won! received [ through Mr, K, Jones, who for the past nine yearn has run a non] nanoturary nt , at. Agnen, and from Mr. 0. Griffiths, RSPCA Inspeotor at Pen&ancr, The MAl'P I V*>l 'j innry Investigation Centre at Truro carried out nome of the post-mortem r uni nations , was renponsible for all the bacterid ogoal findings and provided laboratory and offioe faoilities. Other organisations assisted with analyses of organs and tiusuos, Tho pups . It has been stated that more than 50 pup seals have been found dead or ; dying n the Cornish coast, Mr. Jones hna given details of ?1 reports of seal pitpn in d ifPicul tins, of which lie has personally confirmed ]8, Pour pupc are still alive in his care. Mr, Griffiths lias recorded 18 seals, plus 4 passed to Mr, Jones, One si ch pup, which nubseijuently died, wa3 reoe.ived from tho lslea of Scilly. There is thus a total of <10 reportB conoerning 36 Feals which wore cither found dead or died soon afterwards. There were two reports from September, five from Octolior and the remainder from November and the early part of Dooember. Figure 1 sho,..,n the distribution of the dead and dying pups. Mr. Jones says that ordinarily there are reports of 8 or 9 pops in ' dlfTionltios each year and Mr, Griffiths suggests a dmi] o' ''.igurej thui reports for 196? are more mimerodo than usual. It is not certain to what extent these reports indicate a true increase in the number of dead pups, . The publicity in the looc.l and national press, and on television, hid the I additional effect of causing a greater proportion of dead seals to l>e reported, 1 Pond se.ilij are not usually reported to the RUPCA or Mr. Jones because they are pmt human aid. \ Of the seals whioh died, 9 were subjected to a full post-mortem exami nation and 2 others wore professionally examined. Four living pups were examined at Mr, Jonen* seal oanctuary. One of these, oo.llectod at I'ortrenth im 4 December, was a fst and healthy pup with an estimated weight of about 60 Ibuj it appeared well able to, fend for itself. DSW 026801 STLCOPCB4010763 'v / {. ) t A n1 |.\ip (7Yf-y) t Cultured the rume day ni Codmvy, n n; j,, ,,r,,.i.T e<..in1i Mu-. 11 i.-,,l<' 'I J\'t' ; b'l nnd li *<l nevoral li'j tf-inarV.i: on i in l.-oii_y n i m i) r Id i.lionc iniMiul'.'ii by udu 11 insula on ] uij *: mil tLe.ir i.wn w 11 i c: i t nnlirjt focii- ing. 'J'lt'M`0 v;uro no ui^nu of groOB infliction, Tlii n lies] i;on.M Imvc Ji.itl nnnl I chance of surviving ip the wild. It died from aociil-inl il oaui.on on 5 he cornier, A third pnp won captured at Newquay on 26 November nnd the fourth al 3t, Agnes on 16 November. Thane wore fed on a milk/murg.-irino dint with mackerel. Both woro very much undersized for weaned pups nnd probably weighed about .111 lbs. cnclu Mr Jones thought they were not putting on weight properly annridr.riiig how muoh thoy ate. One had. ntiine superficial eye infection Tiom which the organisms Cnrynobacterluin pyogenes and Fsoudonmu a: nn-ur.; miin we re i| > l.'-il f llolh pupit produced a thick Usual mucus (an did two oJdi-r seals nt the fmnetuary ). Thin tnucun yielded on oulture nn organism of the genus Prot.enn arid Escherichia ooli . It in unlikely that any of those orgnninms wan dirnoUy roijponuiiiiT l or the* jioor condition of the pupn. C. pyogenes is often preumil. normally on mucous membranes and skin; K. oolj and Frstcuo, both enterobacteria, an: widely distributed an non-pathogenic erganimns , but may ounce infectionn, an cn I '.loud (.muuino > The remains of a pup oarnase found at St, Agnes on /\ December wore examined, The animal had henn dead about aix weekB and the head and the anterior part of tho body were missing. Itu weight at death wan estimated at about 20 lbB, It was probably either a still-birth or a starveling which ha.il received no milk from its mother. . The findings of the poct-mortem examination of ten other scale are miniinarined in Tub].* I. One noal (77^9) died from accidental anphyxia. One (6322) wan found to be suffering from pneumonia, hut on]y the lunge worn available for examination. Two (6337 and 1620) war0 recorded an dying from, npptioaemla. The oauoe of death of the remainder was diagnosed as: fi tarvation. With the exception of 7789 which died from accidental cuuses, and ydPO, the body weiglita of the remaining seven animal 11 wcvn all 35 lbs, or Ihsii. The average weight of a Orey real pup nt birth is about 31 lbs, and, under normal feeding, it reaches a weight of botween 90 and 100 lbr.. by its novenle*nth day of life, when it iB weaned (Coulson <? Hicklirig, 1964), Koet Orey noal pupo in Cornwall and the south-west generally are born in Into September and October (Davies, 1957) bo that it iu highly probable all the pups examined were well pan! the age of normal weaning. Thun all pupa weighed (except 1620) were grossly underfed. TV}!, which weighed only 1? ]bn, had the lowest weight ever recorded for a Orey aea.1 pup. 1620 won entlmated to be 65 lb8, but the post-mortein report said there wan "come degree of (starvation". Probably thio estimate wnn muoh too high; a pup weighing 6V lbn 1b plumj: and fat with a well-developed blubber layer and would ultow no signs of starvation. Variouo organiniie were oultured from the Beale eraminod, Encherichia Op]j wan reoovorod from five of the specimens, protoun rip. from one end ntroptooooci from two. These organinmu are probably normally pronent on nots-patliogens, but they cm load to septicaemia (as in 6337) in an animal in >oor condition. Panturollu multocida ( - F. sept icq ) iu pathogenic for a largo number of difforont animals. "1 robably the rnont important role that fn]tnrii]la multocidn plays in disease iD that of n-secondary invader whan the resistance of the animal hue boon reduced by various otreason" (Merchant & Fucker, 196/ pp. 339-340), Fanturolln hnainol.yt i c.a is also an important secon dary invador. An with P. mul tcoida envj ronnienta1 factors are thought to lie important in loading to infection. DSW 0 2 6 8 0 2 STLCOPCB4010764 > Fi-nm Tour of the animals n jcnm i nod no orgitiir.Mit could bo ciiH.im!, This u.'iii I'I'm'1 i.l'l.V dun to l.lio ('fit! bio t,i o therapy tlmy jr-c-n ; v'*d wlii.ii- m f*,- , 11 t), .: cars. .'J,-.i'll)']on of tissues from epeoimens 7843, 7^47 and 7"'/> wore nut)j>oted 1.0 ft virolugiuni examination by the Veterinary 1 riven tj gat i oti Cnntro, Bristol, liesullo worn all negative. The bacteriological finding show that seal doathr. were not dun to f..tiy epidemic disease. The pneumonia. and septicaemia ilingnnsnd pr obably rnpiv... n(Miloti the tormina) stages of a deolinc due* to look of food, rather thnr. the infootioii of an otherwise healthy animal. Diagnoses, weights and bacterio logical examinations Indicate that tlie primary cause of death wan malnutrition. An tho animals examined represent 2`j per coni of the total reliably reported dead ( a very high percentage for an episode of thin kind ) it in juctifiible to extend this conclusion to the mortality an a whole. Possible cannon of thiii starvation are OieouoBed later. ` I 'Hie adult seals at tho Li sard i fleportn were received of sick adult seals at the Lizard, The Seals \ Hesearcli Officer visited the Lizard and interviewed two people who had neon i . those neiiisj the following is a synopsis of their account. A mnnibor of tho crew of the Lizard lifeboat Baw a large seal, about C feet in length, on the old slip on the afternoon of ?6 November. It appeared to be gnnping through its mouth and its nostrils were opening find cloning. Them wan somo white muouo around the nostrils and mouth and the seal wiped at itn face with its flippers. Fetches of fuel-oil vibro present on the body (tills is usually seen on Beals in this area) but on the sides of tl o neck was what \vau dosoribed aB a "burnt patch" where the fur had gone. Thio was not tho oort of mark that oould have boon caused by entanglement with a rope. Tho following day a pup wns seen on the slip. The pup nppm rod to have a noro eyo surrounded by mattery greoBe but it. wan lively and mapped at the lifeboatman'a boots. It ie not usual to see seal pups nt the Lizard but Kynanoe Cove and Soapy Cove usually produce a few pups mch year. On ?8 Noventbor & big Beal was seen witli a raw band around its nock, Tliii; ooal was gasping and its back jerked in n convulsive way. On the aftornoon of 29 November a very big seal was Boon on the olio and wns approachod to within two yards. Its upper lip was rolling' back and its eyes had a glazed nppearance. It wipod its face with itn flippers. Tl 0 animal gave off steam from its Bkin. On Sunday 30 November, throughout tho low water in the middle of the day, a very large seal was ashore on a rock. This was approached to within three yardn. The oeal was lively and aggressive and barked at the lifcboatm:ui > On tho right side of its neck waB a patch about five or six inohos in diameter, from which the hair had. gone.. The skin was 'rising up* and though it wan not bleeding there wea on ooze from it. It was poauiblu to see the flesh and white fibrou. A companion.of tho lifeboutnum, present fit the time and who had been corroborating this account, said that the -lesion resembl'd an over grown osltlo ring-worm. On tho loft nide of tjio neck was a patch of about tho r,nmi! nize. Mere the hair was present but won matted by .1 greasy ami mattery dioobnige, The soul rubbed at these palcihon with itn flippers from time to time, QSW 0 2 6 6 0 3 sI * STLCOPCB4010765 \ d. A) The .11 febo-itm-m thought that tho ]on icon desnri bed w i > not "1-<1 ( n.i i'i hike wounds. II iwi.iil 11 io skin had not been torn. Ilo w.-ui huit that i ']rj adult seals sighted on those four occaniono wore all nop.ir.i to arum ij u, A local fisherman gave a Bitnilar, but lenB extensive, account and I'M that *!<* i cal ooen on Sunday ir/. ht have r. i :. n/a.I. In a Jobs tar pot or & wrok when hunting for broum or confer. Ilona of those seols was seon after Sunday 30 November. A report of seals with "burn marks" round their necks at I-und'c Knd was made to the RSPCA Inspector at Penzance, but the animals could not he located. The description given of these lesions tallies with lesions observed by members of the Souln Research Unit on both Grey and Common neslo off Eant Anglin und in tho Wash, Their aetiology is unknown hut their apposranoc corrospondo with a long-standing ulcerative condition of the skin with baoterial and possibly fungal infection. It is not possible to make a diagnosis of the condition reported in Cornwall as no specimens have boen secured and no qualified personc have Been these seals. A similar ulcerative lesion with necrotic areas hau boen doooribod from tho dolphin Lagenorhynohup obliquidonn (Johnson ARidgwny, 19^9) Pseudomonas aoruginona wan isolated from this lesion; the same organism was identified from the infected ye of n seal in the present investigation. It Beemo most likely that these leuionn are duo to secondary infeotion of a minor wound on a seal that is in poor oonditior, 8uperfioial wounds in seals take a long time to heal nB the lowered okin temperature oausod by immersion in water hindors tissue repair. If the Benin Boat) at the Lizard were bulls, which seems likely as tall wore des cribed ns large, then the neok lesions were on the aron most often wounded during fighting in the breeding Beaeon, The significance of the gasping reported in two of the seals in rot known. Seals sometimes suffer from lung-worma, but this would count! them to oougli, not gasp. If the Deals were nuffering from pneumonia, an a result of loss of condition and subsequent infection, they might show respiratory diBtross. Seals never normally inhale through tho mouth. Some adult deals might be oxpeoted to be in poor condition at the end of tho breeding season, but there is nothing to connect the denoribeH condition of the adult seals at the Lizard with the roportu of dead and dying pups. *' 6 . The question of pollution Mention has been made of public fears of environmental poisoning, aroused by the deaths of sea birds in the Northern Irish Sea earlier in the nutumh of 190(). The oxistenco of a Ministry of Defence (MOlP experimental establishment near Portreath naturally addod to this specu lation about pollution. With thio in mind,'signs of poisoning worn especially look'd for. No ovldenoe has coins to light that either the deaths of Urn pup:: or the oonlition of tho sick adult soals were caused by pollution nr j.cjmning, either chronic or acute. DSW 0 2 6 8 0 4 STLCOPCB4010766 ) 5 There wore1 no uigna of gaotritin or onloritj.n (apart from that nonocintod with oeptlcuemia in two oasuo) in any or tho pupa examined pout-mortnm. Tho description of tho aide adult ooalu doon not allow diagnosis but it io very unlikely that the looionu obnorved could horro rooulted in chronic poinoning. It oould bo opooulntod thut they wore enuned by acute contact with corrooivo oubntanoe, but it is imponsible to oubstantiato or even investigate uuoh a ouggaation with no specimens available, und it ia thought probable that those leoions resulted from infoct.lon of woundo. 1 Timme samples from ^ of the Cornish ue.il pupa were analysed for organophonphorun anti organochlorino reniduca. Ho or;yuioi'honpli<.ri)!! compounds were detected. Organoohlorino compound;-! looki-d for w<>re the pesticides tlieldrin and DDT, tho breakdown products DDE and T:n;f and a croup of substances commonly know as pol.ych]oriti itod bi phony In or rCDfi These oompoundn are oil highly lipophilic and bonce found dinnolvod in the body fo.t* Previous ancay for theno nuluitnnoau in nealu han been by analyeio of blubber samples, but the emaciated 'it t,# of the Cornifih seals allowed only liver to'bo routinely used, though throe blubber samples were also examined, Pcnulta for liver and blubber agree whan oorroctod for fat content (Dee Table Ti). A suckling seal pup rnty; become contaminated with orgonoohlorinoo from residues present in its mother's fat. 3uch rood duos might paes through the placenta to contaminate tho ,foetus bofore birth or tho pup might become contaminated by drinking milk with organoohlorino-opntaminated milk fat. The pooolbility of oontaminntiou through the skin cxiota, but tho quantity whioh oould bo involved in tho course of the pup'o life would be minute. Although quantitative data ore looking it is believed that the great majority of tho organoohlorinoa found in seal pupo thut huvo not begun to food for themselves havo boon ingoated with the milk and that tho contamination found in the pups therefore refineIb tho general contamination of the seal otook. It follows from this that the amount of contamination present in a suckling seal pup depends both on the degree of contamination of its mother's milk and the amount of milk it hue reoeivod. If for any reason lees than tho normal amount of milk is taken, the total dose of organochicrinou obtained from the mother will be smaller than if the pup hnd taken n fhll ration of milk* However, if tho deprived pup then nubuequently starves it will use up whit little fat itlias but not the dlusolved orc^noohlorinep. The renOi of this In a rine in tho concentration of ergenoehlorinpc in the fat* Tho ultuntlon in thus extremely complicated. Truo comparisons bebweon organoohlorino concentrattona cun only bo made t'~ tho nutritional ntatuo of the animaln compared in aintlur. An, all tho Cornish matariul orlginutod from starving pups, a clono of animals not DSW 026805 STLCOPCB4010767 () ) inviuitlgntod in oarlior work, it was decided to compare the Cornish srmploa with material obtained from lj ooal 3 well nourished and 2 starving, taken in January 1 <J']0 from another colony, Tho results obtained (sea Table IT)are not oasy to Interpret. A comparison of values from tho woll nourlohod and otorving fjoaln from the Northern colony Bhavrs that the ooncontmtj on of organoehlorinos found iu highor in the starving pups. An explained ofirllar thin doe3 not imply that tho starving seals have received a greater quantity of organoohlorinos than tho wall nouriohod soals. In fact tlie opposite is the nemo, beonuoo tho utilioation of fat by tho starving animal;) ban oonoentrntod tho organoohlorinos into tho omnll amount of fat remaining. /la neither of tho starving animals from tho Northern oample wan an emaciated an any of tho Corninh orals examined (except for 7799) the concentration effect iu more marked in tho Cornish sealo. On tho other hand, tho well nourished animals from the Rorthorn colory, having roooived more milk fat containing dissolved organoohlorine compounds from thoir mothers* milk, have therefore received a higher total done of organoohlorines. . When the oonoontrationo of tho various compounds in tho tissues are coraparod it iu found that dioldrin, DHT and its derivatives liDE and TDE are found in similar concentrations in ooal rups from both Cornwall and the Northern colony. Qooauue of tne concentration effeot caused by starvation it sooins likely that dioldrin and DDT pollution in Cornwall is not as heavy as in the area from which tho Northern soalB wero obtained. DSW 026806 STLCOPCB4010768 7) The '.nne appears different for PCBs, and Cornish uoaln contain 3 to 10 tlnm more than the soaln from the North but considerably less than sen In from East Anglia, where Grey and Common seels have been found to contain between 3i0 anil 520 p.p.m. PCB in their blubber. The difference found in Corninh eealn in in the proportion of PCBs to other organochlorines, hut it Bhould lie oniphen Ined that the sample is email and the maleiinl (starved pujm) unusual so no definite conclusion oan be drawn. The toxioit.y of orgonoohlorinee genorelly in vary imperfectly kovai. It in believed Unit wlion an animal ir. woll nourished, witli ample fat reuei-vv-, considerable concentrations can lx* tolerated. If the animal's nutri tion il status declines, fat iB metabolised and the dissolved organochl orinen .!) roleaned into tlm bloodj such deleterious effeots on are known concern DDT and diolelrin in birds. PCBs appear to bo lees toxic to birdn than DDT. No information at all is available about the toxicity of organochlorinoB to seals but even the most heavily contaminated Biiirinl3 studied, those from Eaut Anglia which oontained 350-520 PCB, 30-36 p.p.m. DDT and O.0-1.O p.p.m. dicldrin in their blubber, did not appenr to be suffering from ui\y symptoms that could be ascribed to poisoning. The Ministry of Agriouiture, Fisheries and Food in currently carrying out -monitoring programme to determine the level of organoehlori ne com pounds in marine organisms and fish in the South-west, So far no except!otnl ]y high 1 evolo have boon reported. - Other contaminants Other tissue samples from the Corniah nealn were nnnjynnd for traces of the heavy metals, arsenic, lead and mercury. The reunite, together with thono from the control sample of Reals from the necond colony ure net out in Tablo III. The levels recorded are of the same order an has baon roooi'ded from ninilnr organs from other mammals, though the mercury vuluoo appear higher, but there are no data for normal levels in nealn, Dosidor. the three elements listed in the table, a qualitative sc. n wan made for other possible toxlo elements, but nothing exceptional wan dotectad. It had been suggested that the . HOD research establishment at Nanoekuke, on the cliffs above Portreath, might bo the nourco of poisonous effluents, but all effluent from the laboratories at Nancekuke is chemi cally treated to render it innoouous, and it is held in tanks prior to discharge into tho sea. The effluent in monitored both chemically and biol ogically, using marine organisms, before it is discharged. Tho suggestion in thus quite unfounded. "What," asked one national newnpnper, "is the n\yutorioun rod froth in the uen beneath Nanookuko?" These red waters, seen benouth NancckuJ.o, at Oodrovy and elsewhere on the nortli Cornish coast, are caused b,y water running from the adits of the tin minoo after rain. The phenomenon in well known to Cornishmon and the Red River, which discharges into Dt. Ives Hay about n mile nouth of Qodrovy Point, hao receivod its name from this. DSW 026807 STLCOPCB4010769 d.. Itaporto of ohoalB of dead fich wore circulated. These nil appear to ve'-ite t.o a nhoal of young pilchard, found ashore jm.il to tho wool of l'civlon<-liy the keeper of the Pondone llght-honne on 29 October. Tlieno fioh were examined by the District Innpector of Fisheries at Nnwlyn, who riant upecimann to the MAFF laboratory at Burnham-on-Crouoh. These were analysed for organochlorine compound", including PCBe , but no n igni f i mii t ooncentrat i onn were found. It wmi concluded that this uhaul had stranded and imbiioquonl.ly dried out. A report of underBized pollack being oaught Buffering from lenions dencribod no 'burno', both intornal and external, has also been widely circu lated. The Inspector of Fioheriea could not substantiate this report and no upeoimenB wore found. Cod and other gadoid fieheB like pollack aro not infrequently found Buffering from ulcerative leeionB. In tho course of the whole seal investigation only three dead eoa bird:-, were found, and although birds were not espocially looked for, thin seemn a very low figure for the time of the yenr. The lack of reports of dead bird.: in the area Buggeato there was no gross environmental pollution. Later observations at sea To oheck whether the mortality at Cornwall in 1969 approached totality, a fishing veoBel was ohartered on 11 Deoembor to look for surviving imps at known breeding looalitios (Figure 2) , The Carrack rooks, about 3 miles west of St. Ivec, were firBt visited. This is a regular hauling plaoe for Oroy soals in the summer, but is not a breeding oito. No seals, either adult or pup, were neon at the Carracko but ft very heavy ground swell whioh broke over the landing placeci would have made it impossible for the seals to haul out. At the eastern limit of St. Ives Day a young seal wan eeen in tho water about 100 yards to the north of FiBhing Covej although otained with fuel-oi.1 and rattier thin about the neok it was not obviously sick. Another young sea.1, was seen swimming vigorously in the surf to the weBt of Hell's r.outh. At Crane Island a young Beal was oeen olose to the rocks, and another was seen off Samphire Island and two more nightingn were m:-.de at Kulph'o Cupboard. It is possible that these were of the same animal* Another young seal was seen just to the west of Gull Rook. At Gull Rook the tide forms an eddy where flotBam and the bodies of dead animnlB aoouraulate, aooording to fishermen with looal knowlodge, Mo dead seals were seen here, but two oiled guillemots were picked out of the sea. The sighting of eix or more, probably seven, young seals off the coast between Oodrevy Point and Portreath. indiontoa a fair survival of pups, on the basis of summer sightings cf adults. Only one of tho animaln ueon (tlift first sighted) did not appear to be in a perfectly healthy condition, but some fur"hor mortality of ydung might be expeoted in the oourao of the winter. No adult seals were seen during the trip} they were probably lying up in tho oaves. DSM 026808 STLCOPCB4010770 DJ fIClIBBlon Tho primary oaune of death of tho peal pupa fouivl on the Cornish ooast was starvation, thought to havo boon oauciod hy tho pups becoming nsp/tiMled from tJigti1 mothers before normal wooning timo. The lactation period in Oroy noals iu vary ohort, lonting loon than 3 wed:!. The mother then deserts her pup which fastc arid Jones wo i/-lit, boforo baginn- Inc to fend for itself. Uhile it sucklaythe pup pula on woighl nt an autonisliing rate, ao muoh an 51 lbn/day being recorded (Coulnon A lliokling, ly64) thouch probably around 3-4 lba/day io more unual. The link between the pup and itn mother, ito only souroe of food for the first three weeka of its life, is a dolioate one and should it be broken earjy tlie pup's chances of uurvival aro greatly dooreaoed. It is believed that a pup which linn not readied a weight of around 65 lbs by its lout milk feed io unlikely to survive the winter following itn birth. Cov/ seals are known to lose contaot with their pups an a result of bad weather or disturbance through orov/ding effeots or human interference. Crowding does not nooessarily involve largo numbers of oealrt; oven a small number of nenls in a oonfined space may constitute a orowd and disturbance to normal behaviour may follow, oo that mortality through cows losing contact with their offspring is by far the oommonest cause of pup death on Grey seal breeding grounds. Starveling pupe wander about trying to feud indiscriminately from cows, or even bulls and other pups, and aro frequently savagoly bitten. Infeotlon of these wounds may ooour as tjis pup's condition falls and eventually death may result through septioaemia. The localities on the North Cornish ooast wtare seals nre found are all exposed to northerly or westerly weather and most, if not all, the pups pro duced' in this area are born in the nea-oaves. Although the caves offer some proteotion from the' weather, the spaoe inside may be limited, particularly at high tide, and orowding of the type mentioned above may occur when oven only half a dozen seals use a o&ve. A pup whioh strays outside ito cave nv\y well have great difficulty in finding its way baok again, particularly if the entronoe to the oave io boneath the water. It is probably the laok of good breeding sites whioh hus limited tho Grey seal population in Cornwall. Crey sealn occur most abundantly where the breeding fomales have aooess to sheltered boaoheB or low grannlands behind a beaoh. fiy far the largest conoentration of Orey seals in tlio South-wont in that oentored on the tip of Pembrokeshire, from Strumble Head to Caldey Island, This area, together with part of the Cardiganshire ooast, supports a population of about 300 pups, of whioh rather more than half are born on the iolandn of Ramsey and Skomer. About 200 Orey seala live on the Scilly Inleo, mainly on the rooky islets to the west o'f the inhabited islands and about 60 pupo are produoed each year. The numbers inhabiting Cornwall nro less oertain. The seals are considerably more dinpersed than at either tho Scillies or Pembroke and it seems likely that their numbers are addod to in the summer by animale from the Pembrokeshire colonies* However, o figure of 200-?rj0 seals for tho Cornish ooaot from Hartland Point round Land's End to tho Lizard seems reason able. Such n population would produoe about 60-75 pupa oach year. DSW 026809 STLCOPCB4010771 .l) 10 ) Ah it wan o orieludo.d that about 40 pups were reliably report'd ili*-i<i tbi*rn wore probably ioii<c do ad animals which Wero not rounil (though i 1. ia thought that them' w7'o vary row) thin v/ouid represent u high mortality i f all the pupa n.iinf from tlm Ccrnliih ntook, flrey i)*<iln are long-lived nnlmals, life spans of up (<> 40 yearn 1 i-iin/r record ml* They lwve few prod/itors other than man and tlm .idult mortality r it'*, in the nbnnnoo of human interference, lu thuu vnry low, High juvenile, morlnli t.v imI.imi, on the other li/inrt, /ire the rulo at Gray Beal breed in;; colonier. On the Lanin of existing life table data (Hewer 1964) it ban L/*<*n aurunmd that on Jiveraga 60,1)'> of all pups die in their first yeur, mostly noon nftor birtli jukI weaning, There Id, of course, year to year variation and population/, brood ing; /it tho foot of oliffs are very liable to total mortality of tho pupa in li.ul weather. A opell of heavy westerly weather 1b believed to lu:vo killed nearly all tho pupti born at a breeding site under the cliffB of Honan Hill in Shetland In i960. . In Cornwall, uoals are very little, if at all, molested by /nan, Killer whalen, virtunlly the only eeal predator in English waters, aro rarely Been off Cornioh coasts. Ae tho Cornish seal stocks do not show u rate of increase comparable to that observed in the pant quartor-oentury at other Grey Heal col onion at, for example, the Fame Inlands or the Orknoyn, it its concluded that lhe jnvonile mortality rates in Cornwall inunt,.on average, bo high. The prob/ihlo rnn'jon for this ie the laok of suitable breeding sites on the 'inhospitable Cornish ooant. There ia a ponsibility that not all the pupB found dead originated from Cornwall, and the much larger Pembrokeshire population Beonw a likely source. Many young seals in Pembrokeshire were marked between 199? and 1969 by the Went Wales Naturalists Trust and of tho 62 marked animals recovered outiiidc the marking area 20 have boen rooovored on tho South-west Peninsula; one from the Soilly Isles, 15 from Cornwall and 4 from Devon, Of tho ?rj animalt; marked in 1969 one hau already been reoovered from Cornwall. Table IV shows the inoidenoe of windo of over 20 knot;; (correoponding to slightly more than Pore 6 on the Beaufort soale) as reoorded at Milford Haven and St. Hawgan in September, October and November 19^9* Winds of thin speed could create sea conditions bad enough to oause some pups in unfavourable uituations to booome separated from their mothers. ; Between 7 and 9 November strong winds blew from between west slid north (Table V) with speeds of up to 41 knots. All but 7 of the 40 reports of dead /uid dying pups follow this period of bad weather, no it m.mm likely that bouio of the animals reported oould liavo been driven by tho wind from Pembrokeshire to the Cornish coast. It may bo noted hero that there was no similar reported mortality of scale from the Pembrokeshire ooast. Only two sickly pups had been noted ;<L Dale Port Field Centro by 10 December and a representative of the l/cot Walon Naturalists' Trent oouuiders that tliore /ire only five reliable rocorilr. c>l' Heart or dying pups, four from around Manorbier /uid one from Tenby (Fig. l). H in highly likely that other deaths occurred whioh wore not reporlod but it iu certain that there was no exceptional mortality in Pembrokeshire. ' r OSW 026810 STLCOPCB4010772 :u Summary and Ccmclurnon ,) About 40 reports of dead or dying flrey oal puprt on tho Cnnac.h oo:'t between Newfjuny tuid Fowey wero reoeived in the autumn of 1909. (Cloven of tlio dond uealn were examined, of whioh 9 worn subject*; of full print--mor. Tho oauno of death wan determined to bo starvationj no evidenco woo found of an epidaiido. Four adult seals soon at tho Lizard at tho end of November had lonioru; on their nooks. Thane losiono are believed to bo the result of woundn, reooivod in fighting during tho brooding neaoon, becoming infected. An&lyoos of linnue samples of tho dead scale nhov; that the Corninh seal ntooku, like thono from elsewhere in tho British Icier., arc contamnu-Urt with organochlorino residues. The level of pesticide (DPT and dioldrin) contamination is relatively low but PCB contamination in relatively high, thougli tnvtoh lower than in oeals from East Anglia. The ooncontrution of lead and arsenic in tho Comioh saal pups is of tho same order as that found in other mammalo. Moroury levels are higher; The seal pupa whioh were found doad or dying had become separated from their mothers before the normal weaning time which is about tlireo weeks after birth, and had been insufficiently developed to start feeding for them selves, The ooparation was probably oaused either by disturbance or bad weather. Healthy pups wore still to be found on the Corniuh coast after the last of tho reports was received, Somo of the pups reported from Cornwall may have originated from Pembrokeshire. A spell of high winds in early November might have cauned pups to drift from Pembrokeshire to Cornwall. . It io ooncluded that the deaths were part of the normal juvenile mortality of tho eoals, always likely to be high in Cornwall, and that extraneous faotorB such as epidemios or pollution) were not involved. Vf. Nigel Bonner Sealo Rosearoh Officer Seals Hesenroh Unit: Lowentoft. DSW 026811 STLCOPCB4010773 TabJo I Summary of po3t-mortc3n roports ______ on ton Grey ooal uupa 8of.No. Dulo oxwninod Sex Weight Diagnosis Organisms cultured 6022 27.10.69 F. lungs only Pneumonia Paolurella multooida GU07 27.10.69 M. 30 lbo. Septicaemia 1 7397 19.11.69 F. 12 lbs. Starvation Pnsturellu multocidu Escherichia coli - '{(>?.0 20,11.69 F. 7634 29.11.69 - 7717 3.12.69 F. 7789 0.12.69 7043 " 9.12.69 7047 9.12.69 70*32 9.12.69 F. P. M. 11, (65 lbs) Septicaemia} Bomo degree of starva tion 25 lbs. Starvation (pneumonia) 22 lbs. Starvation 42 lbs. 22 lbs. Asphyxia Starvation 35 lbs. Starvation 33 lbs. Starvation Escherichia coli - PastourelJa haemolyt^cn Escherichia coli Streptococci Escherichia ooli Proteus sp Escherichia ooli Streptococci ' - * eotimatcidveight DSW 026812 STLCOPCB4010774 r-------------------- Tissue Origin Pat content per cent Cornish 5.2 Conceatration in tissue, ppa wet wei.^t Bieldric ICE tie 3DT Total insecti cide orgsncchlorine PCS 0.08 1.9 0.31 0.22 " 2.51 46 Lirar Northern (well nour ished) 9.Q 0.07 0.5 0.09 0.5 1.16- 3.7 Northern (starving) 7.6 Cornish 16.7 0.07 0.25 1.0 0.15 6.7 0.69 0.9 2.12 6.2 3.7 11.34 160 Blubber ! northern (well nour ished ) Northern (starving) 86.2 0.38 4.7 0.66 4.4 10.14 34- 73.3 0.57 1.16 | 9-5 7.4 18.63 46 -- Table II Synopsis of concentrations of organochlorine compounds in seal tissue. (For full details, see Appendix). * DSW 026813 u) table m Coiieen trtioni.i or Aroonic, IkuvcI <Tc i.lorrmry in Koa'J tionuen, oxjiri.-fjijod ut3 inicrorrn/nu per (irnadry weight or tinnuo. (Annlyaou by 11.11 - Allon, Merilovroocl -iooonvch LltaUon, iluturo Coiioorvniui.y, Orniyio-ovor-Onmlri , Lnricnnhiro),_____ Conoontrntion,i^ii dry woi/'.ht Spooimon No. ( 7843 ( 7047 7852 | 7620 !u [ 7034 `g j 7709 S\ (1) Tinous Liver 1 Livor Kidney Livor II II M Areenio P" * ........... -- Lead l.lorcury 20 54 ' 3 15 8 1 10 29 1 <1 1 <i 5 4 3 2 5 5 13 12 0 9. 7 11 ( HO63 ( > 11066 -H l (<09 fl HQC7 SJ11064 S} 4* \ 11065 Liver Kidney Liver Kidney Liver Kidney Liver Kidney Liver Kidney 17 42 <1 11 3.5 3.5 20 <1 15 <1 ........... 2.6 3 4*9 5 3.5 6 2.2 <0.f. 0.6 4 1.4 5 4.1 1 2.1 6 4.3 3 1.4 3 -- DSW 026814 < STLCOPCB4010776 (...) ) Tnblo IV Humber of hours in the month with recorded windBpeodti of 20 linoto or over ut lit. Mowr.nn and Milford Hnvon. (fata from Meteorological Offi co) St. IJawgnn Milford Haven Soptomber 3 . 30 Octobor 31 20 November 171 70 Table Y Averngo wind speed and direction for three de^yo in November, 1969, at Bt. Mnwgan and Milford Haven, (-data from Meteorological Office), November* 7B9 St.Mawgun* Speod Direction 19.3 343 24.7 208 20.2 272 knots docreoa Milford Haven* Speed Dirootion 12.0 330 15.0 206 17.9 271 knots degroen DSW 026815 STLCOPCB4010777 List of Fjfiaron PiQ.1* Mup to show distribution of reports of doad and dyiiy; seals on tho Cornish coaot. Five similar roporto .from Pembrokeshire are alBO shorm. Fig.2. The coast seorohed for youn# sonla. OSW 026816 STLCOPCB4010778 JlcforcncoH Coulnon .T.C. L Hiokling G. 1964. The breeding biology of the Groy ooul, Hallchooriri gryvufl (Fab.) on the Fnrne InlnmlD, Northumberland. J.Anim.lScol.^ 405-512 Davion J.L. 1957* The goography of tho Crey aoal. J.Mammal. ^ (3) * 297-310 Honor H.R. 19M The Determination of ago, eexual maturity, longevity and a lifo-table in the Grey eoal (HaliohocruB flrypuo). Proc. zool. Soo. Lond. 142 (4) 1 593-624* Johnston D.G. & Jlidgwegr S.H. 1969* Parasitism in some marine mammals. J. Amor. vet. mod. Assoo. 155 J 1064-1072 Merchant I.A. & Packer H.A. 1967* Veterinary Bacteriology & Virology. Iowa State University Press. Araer. Iowa. 7th ed. 1967. X + 752 pp* . DSW 026817 STLCOPCB4010779 Conocntratiotw of or^nnochlorino compounds in non] tiiiuuna, expressed no fuu-tc por mil] ion, net weight of tlfinuu. (AjuilyuoB by A.V. Holden, Kroshwator Kinherien laboratory, lXi(i;a.'tmont of Agriculture & Fiohorieo for Scotland, Pitlochry, Perthshire.) Bprcbnon ho. Ticsuo Pat Content per oont Concentration in tieoue, p.p.m. wet weight "1 " ` T %Dieldrin DDE TDE DDT PCB ( 7041 ( 7047 ( f ;n::0 P,.v Yi.34 a( vw ... ( (1) m( .,1 Avorufie .3} ______ : $ 7043 ) 7047 > 7052 Livor II 11 11 II II II Blubber II II &v ora;? e 4-3 2.3 4.5 4.1 11.1 2.6 6.7 5.2 37.5 0.2 4.4 16.7 < 0.01 0.07 0.11 0.05 0.15 0.04 0.11 0.08 0.44 0.23 0.06 0.25 0.9 1.8 . 1.2 1.0 1.6 1.0 5.1 1.9 0.15 1.3 0.57 < 0.04 < 0.02 < 0,02 < 0.04 0.31 8.7 1.1 8.1 O.69 3.2 * 0.27 6.7 0.C9 0,4 0.1 0.0 < 0.03 < O.O4 <; 0.04 < 0.00 0.22 4-5 5.0 1.7 3.7 17 36 77 31 43 26 90 46 173 187 118 160 ( H063 ) H066 ( II067 Liver II II Avuraf'o ( HG63 } 11G66 HG67 Jy /1Average Blubber ti If ? 7 IIG64 / 11065 VOi l} \Avtlrnf5e } HG'64 > HG65 /Averrv.o Liver It Blubber II 10.0 9.2 7.9 9.0 64.7 87.4 66.6 66.2 7.4 7.8 7.6 80.4 67.1 73.6 0.04 0.11 0.07 0.07 0.37 O.58 0.20 0.30 0.05 0.08 0,07 0.54 0.59 0.57 0.7 0.5 0.3 0.5 6.0 4.9 3.3 4.7 0.7 1.3 1.0 10.3 0.6 9.5 O.O9 0.09 0.09 0.09 0.86 O.65 O.46 0.66 O.09 0.21 0.15 , 1.17 1.15 1.16 0.7 5-2 ) 0.4 3.0 0.3 2.2/ .; Hi0.5 44 \ 6.5 4-1 34 M 2.6 *5 3 \ AS / re 4.4 34 ) 0.6 3.9 ) 1.2 0.4 ) 0.9 6.2 { C> - yO 7.6 50 js 7-2 7.4 ' 40 j DSW 0 2 6 0 1 8 STLCOPCB4010780 Of ^ JL . H (\ p 12) dxi. ^rv bw/vie-vv oj 'i'tpKyCk cj'dt'CxA & cLjU^ r\\k*i Corn\tk ^OCvlfc , five* s>f*v'< (av 'Tt'^Otfe J.yfn-W QnJ>*fcfUfVv ave. cvhc. 3Acv|vt. f 0SW 026819 STLCOPCB4010781 STLCOPCB4010782