Document NEjxEm7rXd8q7Bzm3KR9ZNEv8

Vj-6>. -- St, L^qoiS Sanl Deaths in Cornwall Autumn 1969 r~~ l i j i t l1 ! DSW 038131 STLCOPCB4021955 Fr>r<: >:. rd Tho oecurronce of doathfl amongst seal pupo in Cornwall in the autumn of was investigated `by tho Eoalo Kenyarch Unit of N 3-U-C. The* Office in Charge of tho Soal3 Ronearch Unit gave interviews to t'nr* press and info.-med thorn of tho progruoc of these investigations, Uow that th-.-se are complete, w thought it would, be in tho best into rents of everyone if an extenoive account wor-v produced. Tho following report is not in the strict form of a scientific paper and is somewhat rcore discursive; it io hoped that those receiving it will bear this in mind. Nevertheless, the investigations reported ar.d the con clusions reached .'iave been pursued with the utmost scientific rigour. Aclrr ovj 1 od gome ntg The Natural Environment Hasearch Council (DBS C.) and the Sealo Research Unit are much indebted for the help they received from people mentioned in the report , and in particular, for the co-operqtion they received from Mr. Jones, who runs a seal sanctuary at'5t. Agnes in Cormrall, and the Royal Society for -the Prevention of Cruelty to Animals (Jt 5 H C A ). Tho facilities; accoruod by the Ministry of Agrioulturo, Fisheries and Food (U A F F ) locally wore 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, and to Mr. >. Allen of the Nature Conservancy's K.crlewood Research Station for the cbemioal analyses. DSW 036132 STLCOPCB4021956 Considerable public concern who oxprennod in the autumn of 1969 fol lowin;; report?* of dead find dying seals being washed up on' Cornws.1 3 nhorec. flu* reportr. referred mainly to young seals but also to adult seals suffering from lornojiM which were described ho ''burn marks". These reports followed closely oil the reported deaths of around ten thousand guillemots nrnl other birdo of the auk family in the region of the Northern Irish Gea in Eeptcmb^r and October. . Homo nf the no birde wore found on examination to have higher levels ofr.ome orgusochlorine compoundn in their livers than ore normally detected inroutine moni taring,, and thin load to suggestions that the Deal deaths might beniinilarly connected with pollution. Tim NEI1C Sealw Henearoh Unit investigated tho event with the help of various other organ i cat ions and people. Most reports of reals were received through Mr. K, Jones, who for the past nine years has run a ne/*lsanoturary at fit. Agnew, and from Mr. 0. Griffith*?,HSPCA Inspector atPenzance. The MAKF V<.'i i-inary Investigation Centre at Truro carried out some of the post-mortem ,,.> uni nations , wan responsible for all the bacterial ogcal findings and provided laboratory and offioe facilities. Other organioation assisted with annlyons of organs and tissues. , The pupa It has boon stated that more than 50 pup seals have been found dead or . _ying on the Cornish coast. Mr. Jones hno given details of ?1 report 11 of peal ipn in difficulties, of which he has personally confirmed in, Pour pups are ..til.) alive in hiB care. Mr. Griffiths lias recorded If) real?!, plus A passed to Mr. Jones. One Rich pup, which subsequently died, wa3 received from tho Inins of Scilly, There is thus a total of 40 reports concerning 36 seals which wore either found dead or died soon afterwards. There were two reports from September, five from October and the remainder from November and the early part of Dccembor. Figure 1 bIiows the distribution of the (load and dying pups. Mr. Jones says that ordinarily thero are reports of or *) pupn in difficulties each year and Mr, Griffiths suggests a similar ''.igvre; time j"ports for 1969 are more numerous 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 local and national press?, and on television, h <d the additional effect of causing a greater proportion of dead ueala to lie reported, iw.d scale are not usually reported to tho RGPCA or Mr. Jones because they are pint human aid. Of the seals which died, 9 were subjected to a full post-mortem exami nation nnd 2 others were professionally examined. Four living pups were examined at Mr. Jones' neal sanctuary. One of these, collected at Portreeth 01 A December, was a fat and healthy pup with an estimated weight of about 60 Ibnj it appeared well able to, fend for itself. : ' f ! i ; | . ! i } ; } j t CSW 038133 I I STLCOPCB4021957 f A i.ii.| |.I1|) (YYf'.y) , captured tin* iwuiir 1oy at God r< yy , im:; j,, ,r e<,nd i ) i t.,:# i I, i.-'>, ;-lir-ft AP il/i and h;,d several bj te-tiyu-l'i: on its body , n i ini J.~r to Uinr.i i jn" I < c l' ai by adult no.-da < >11 pup'i not tli".ii' wn which solicit feed ing. There K'>r<> no oignu of gross infcctdon. Tin!* non] would hove had r=ii:-'i1 l climes of nurvjving in the wild. It died from accidental csuuum on 5 December, A third pup was captured at llewquay oh 26 llovrmber and the fourth at 3t Agnes on 16 Kovombor* Thono wore fed on n milk/margarinc dint with nifittknrol. Both wcro very riuoli undernixod for weaned jnipn and probably weighed about ;.() lbs. each. Mr Jones thought they v.'ore not putting on weight properly conridi.-ring how much they ate. One had nome superficial eye infection from which Min organ i s inn Corynobacterium pyo/^wicn and. Pseudonion-< s . i e rug1 m>:; o. were in<>! a ted f Both pups produced n thick; nasal mucus (au did two older Renin at the f)anctu;r.v). Tliifi tmicun yielded on culture an organinm of the genus Protenri and Escharichia ooli. It in unlikely that any of those organJemu waa directJy responsible l or thn poor condition of the pupn. C. p.yoaenoo is often present normally on mucous membranes and akin; K. col i iind Proteus t both enterobacteria, arc widely distributed an non-pithogonic organisms, but may enure infeotionn, an can ) '.!(nd oiiit mas The remains of a pup oarcaoe found at St. Agnes on /\ December wore examined. The animal had been dead about nix weokij end the head a.pd the anterior part of the body were missing* Its weight at death wan estimated at about 20 lbs. It was probably either a still-birth or a starveling which had received no milk from itn mother. , The findings of the poct-mortem examination of ten other seals are riumtnarised in Table I. One seal (7?$9) died from accidental aephyxia. One (6P>22) was found to be suffering from pneumonia, but only the lungs wore available for examination. Two (66H7 and 762G) were recorded as dying frow. septicaemia. The cause of death of the remainder was diagnosed ay r.I.ru-vation. With the exception of 77^9 which died from accidental cause.*), and '/iiPOt the body weights of the remaining seven animals were all 35 lbs. or less. Die average weight of a Grey neul pup at birth in about 31 lbn, and, under normal feeding, it reaches a weight or hotwoen 00 and 100 lbs, by its nnventoi*nth day of life, when it is weaned (Coulson A* Hichling, ^ost drey neal pupn in Cornwall and the couth-west generally are born iii late September and October (Davies, 1957) o that it ia highly probable nil him pups examined were well pant the age of normal weaning, Thuii el) pupa weighed (except 7620) were grossly underred. 7397 i which weighed only 1? lbs, had the lowest weight ever reooi'dcd for n Grey seal pup. JC?G wan estimated to bo 65 lbs? but the post-mortem report said there wan ''some degree of starvation". Probably thin estimate wan much too high; a pup weighing 65 lbn 10 plump and fat with a well-developed blubber layer and would nhow no signs of starvation. 1. Various organisms were cultured from the seals synminod. Kncherichia 0011 wan reooverod' from five of the spec!menu, Protons up. from one and ` streptococci from two. These organ isms nr-o probably n:*m-ill.y preaent an non-pathogens, but they cm lead to nopticaemiu (as in (>88f) in an animal in ooor condition. Pasture! la mul tnci.da ( P, sept tea ) tn pathogenic for a large numbor of different nnimaln, "1 reliably the most important role that PanjLnrolla multoeIda ploys in disease io that of n secondary invader when Lite resistance of the animal has born reduced by various strew.-ea" (H-rrluint & Taukur, 1$>6/ PP* 339~3>1f0. Pauturo3 la hueiuolytica is also an important secon dary Jnvador. As with P. mul U^iea environments] le.ctorn are thought to t'p imjiortant in leading' to infection. DSW 038134 STLCOPCB4021958 Knur. four of 1.1m miimalo examined no or,';an in mm could bit ciiHih'm!, This o oi i-i'o' -bl.v due to tho anti biotic therapy tlmy had jocmv'd m I*r ,U h< s' IMF'., Campion of tissues from specimens 7^,/)3 7*47 frtJ 7"`>? were subjected t,n t\ virologies 1 examination by the Veterinary Inves ligation Centre, Jirintol. HnnuHu worn all rotative* T)i* bacteriological findings show that rohI doathr. were not duo to nny epidomir disease. Thu pneumonia. and eepticfirmia diagnosed probably reprenfliilral the tormina] ntropjH of a decline duo to look of food, ratlinr than the infection of an otherwiuo healthy animal# Jiiagnosen, weights and bacterio logical exiiininationn indicate that the i>rimary cau/io of death wan Malnutrition. An tho animals examined represent 2'j per cent of the total reliably reported dond ( a very high percentage for an episode of thin kind ) it in justifiable to extend t.birj oonolunion to the mortality an a whole. Pnnsible Cannes of thiu utarvntion are diecuuned later. 'Mie adult neala at the Lizard Heports were received of sick adult nealn at the Lizard. The Seals Hnsearch Officer viHited the Lizard and interviewed two people who had neon these nenls} the following is a synopsis of their account. A member of tho crew of the Lizard lifeboat saw a large seal, Rbout 6 feet in length, on the old slip on the afternoon of ?f> Ilovombcr. Tt appoarcl to be gasping through its mouth and itn nostrils were opening and cloning. There was some white mucus around the nostrils and mouth and the seal wiped at its face with its flippers. Patches of fuel-oil whre present on the body (thin is usually seen on seala in tills area) but on tho sides of ti e neck wan what was doscribcd as a "burnt patch" where the fur had gone. ThiB was not the sort of mark that could have boon caused by entanglement with a rope. Tho following day a pup was seen on the slip. The pup appeared to have a nore eyn surrounded by mattery grease but it was lively and mapped at the lifeboutimin'8 boots. It is not usual to see oeftl pups at the Lizard but Jy nance Cove and Soapy Cove usually produce a few pups each year. On November a big seal was seen with a raw band around ita neck. Thin ooal was gasping and its back jerked in n. convulsive way. On tho uftornonn of 29 Novomber a very big nenl was seen on the olin and wen approached to within two yards. Its upper lip was rolling hack and its eyes had a glazed appcmx'anco. It wiped its face with ill; flipporn. Tie animal gave off steam from its skin. j On Sunday 3^ November, throughout tho low water in the middle of the day, a very large oral was aohoro on a roc);. This wan approached to within three yards. The coal wan lively end aggressive and harked at the lii'cboitnmn On the right side of ito neck wan a patch about five or six inches in diameter, from which the hair had gone. Tho skin was 'rising up' -oil though it wan not bleeding thorn was an ooze from it. It was poeuib.li* in see tl.ollesh find i-'iii t<* Cihven. A companion, of tho 1ifboatman, present at the time arid who had been corroborating thin account, on id that the ler.jnn resembl'd an over- gi f.'.in r.'i Hie ring--worm. On the loft nide of the neck was a pitch of about the ram. size. Here the Inir wan present but wap mat-fed by a greasy and mat'ery diccJ'.uv'o. Tho coal rubbed at those palehei. with itn flippers from lime to lime. '. DSW 038135 STLCOPCB4021959 TIi#* 11 reboaturm thought that the loniomt described wr>- no!, mil i nary l>i!,e wounds. Ho said the nkin lul not been torn. Ho u.ut sure that I ho nrtult no.iln sighted on those.four occasions wore all uepnr.it animalu. A local fisherman gave a similar, but less extensive, account. and tli.it *!' oal soen on Sunday iri.'.Lt have c ;u''M i'*,' nmh In a lobster pot or a wreck when hunting for bream or confer. Hone of those seals was soon after Sunday 30 November. A report of seals with ''burn marks" round their neck.': at I.jnd'u End wne made to the RSPCA Inspector at Penzance, but the animals could not be located. . The description given of then lesions tallien with lesions obuerved by members of the Soalo Research Unit on both Gr<*y and Common seals off East Anglia ond in the Wash. Their aetiology ie unknovm lmt their appear ance corrospondo with a long-standing ulcerative condition of the skin with bacterial and possibly fungal infection. It is not possible to make a diagnosis of the condition reported in Cornwall as no specimens have been secured and no qualified persona have aeon these Beals. A similar ulcerative lesion with noorotic areas has boen doucribed from the dolphin Lngenorhynchus obliquidoim (Johnson ARidgway, 1969). Pseudomonas aeruginoea wan isolated iron this lesion; the same organism was identified from the infeoted eye of ft seal in the present investigation. It seems most likely that these leuionn are duo to secondary infection of a minor wound on a seal that is in poor condition. Superficial wounds in seals take a long time to heal aB the lowered skin temperature causod by immersion in water hinders tissue repair. If the seals seen at the Lizard were bulls, which Beams likely as nil wore des cribed as large, then the neck lesions were on the area most often wounded during fighting in the breeding season. The significance of the gasping reported in two of the' seals is not known. Seals sometimes suffer from lung-worms, but this would causa them to cough, not gasp. If the seals were suffering from pneumonia, as a result of loss of condition and subsequent infodtion, they might show respiratory distress. Seals never normally inhale through the mouth. Some adult seals might ,be expected to be in poor condition t the end of tho breeding season, but there is nothing to connect the described condition of the adult seals at the Lizard with.the reports of dead and dying pups. *' The question of pollution Mention has been made of public fears of environmental poisoning, aroused by the doatha of sea birds in the Northern Irish 5nn earlier in the nutumh of 1969* The oxistence of a Ministry of Defence (M01>' experimental establinhment near Portrcftth naturally added to this specu lation about pollution. With this in mind, signs of poisoning wore especial l.y looki-d for. No evidence has come to light that either the deaths of the pup:: or the condition of tlm sick adult soals were caused by pollution oj i<>jrnning, either chronic or acute. OSw 038136 STLCOPCB4021960 5 There wore no signs of gastritis or onlcritj.o (apart from that associated with septicaemia in two casus) in any of' tho pupa examined pout-mortem. Tho description of the uiti:adult seals doon not allow diagnosis but it to very unlikely that the lesions observed could hare resulted in chronic poisoning. It could bo apooulntcd thut thoy wore enuned by acuto contact r/it)i a corrooivo substance, but it is impossible to substantiate or <yen invos bigate ouch a Digestion with no specimens available, und it is thought probable that those leoions resulted from infoct.ion of woundo. . Tiaime samples from 7 of the Cornish seal nupn wove analysed for organophonphorun and organochlorine residues* bo org-inopbosphornn compoundB were detected. Orgnnocblorino compound:* looked for v?>re the pesticides dieldrin and DOT, tho breakdown products *)D1S and TDE, and a group of substances commonly know 03 polychJ orj mted biphony In or reiki. These oompoundn are oil highly lipophilic and lienee found dionolvod in the body fat. Previous nnssy for these substances in seals ban been by analysis of blubber samples, hut lbs emaciated at-- le of t)ie Cornish seals allowed only liver W be routinely used, though throe blubber samples were also examined. Results for liver and blubber agree when corrected for fat content (.'Joe Table Tl). A suokling seal pup may become contaminated with organochlorineo from residues present in its mother's fat. Such residues might pass through the placenta to contaminate tho .foetus before birth or tho pup might become contaminated by drinking milk with organoohlorino-cpntaminated milk fat. The possibility of contamination through the skin exists, but tho quantity which could be involved in the course of tho pup's life would be minute. Although quantitative data ore litoklng it 1b believed that the great majority of the organoohlorinos found in seal pups that have not bogun to feod for themselves havo boon ingosted with the milk and that tho contamination found In tho pups therefore reflects tho general contamination of the seal stock. 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 tho amount of milk it has received* If for any reason less than tho normal amount of milk is taken, the total dose of organocbleriueu obtained from the mothor will be smaller than if tho pup hud taken a l'Ull ration of milk. Howovr-r, if tho dej'ii'M-d pup then subsequently starves it will use up whit lit! le fat it lias but not the dissolved nrg">noohlorinep. Tho remii. this In a rice in the concentration of ergnnoch.loriwpe in the fnt. Tho (iltuntlon is thus extremely complicated. True comparisons betwcon organochlorino concentrations can only hr* made l*' tho nutritional utntuM of thn nninaln Ofxnpuivwl j:i ain Liar. As, all t)io Cornish matoriul originated from starving pups, n clans of animals not * DSW 038137 STLCOPCB4021961 6 investigated In earlier work, it was decided to compare lh Cornish wviiplon vrJth material obtained from 5 soal pups, 3 well nourished and 2 starving, taken in January lyfO from another colony* Tho results obtained (see Table IT)are not oany to interpret. A comparison of values from tho roll nourished and starving noalo from tho Northern colony shows that the concentration of orgunoohlorinoo found io highor in tho starving pups. An explained ofirlier thin does not imply that tho starving seals have resolved a greater quantity of organochlorinon than tho well nourished ooelo. In fact tiw oppoaito is the case, because tho utilisation of fat by the starving animals h.-io concent rated tho organochlorinno into tho small anoint of fat remaining. A neither of tho starving artimuls from the Northern aampla was as emaciated as any of tho Cornish seals examined (except for 773?), the concentration effect in more marked in the Cornish seals. On tho other hand, tho well nourished animals from tho Northern colony, having received more milk fat containing dissolved organoohlorine compounds from thoir mothers* milk, have therefore received a highor total dose of orgsnoohlorineB* . When tho concentrations of tho vorioun compounds in the tissues nro comparod it io found that dioldrin, DDT and its derivatives UDE and TUB are found in similar concentrations in seal pups from both Cornwall and the Northern colony. IJocauue of tne concentration effeot caused by starvation it soorns likely that dioldrin and EDT pollution in Cornwall is not as heavy as in the area from which the Northern seals were obtained. osw 038138 STLCOPCB4021962 7. The ('.'inf? appears different for PCRn ? and Cornish seals contain 3 to 10 timori more Mian the Benin from the North but considerably Jeon than seals from East Anglia, where Grey and Common serin have been found to contain between 350 fiml 520 p.p.m. PCB in their blubbor. The difference found in Cornish seals in in the proportion of PCBa to other organoohlorinec, but it should be emphasised that the sample ia email and the material (starved pupu) unusual ho no derinito concluoion can be drawn. The toxicity of organochlorinos generally in very imperfectly Known# It in believed that whon an animal in wall nourished, witli ample fat reserves, considerable ooncentx'ationn can bo tolerated. If the animal's nutritional ntatmi declines, fat is metabolised and the dissolved organochlnrinen are released into the blood; such deleterious effects on are known concern PUT and diolclrin in birds* PCBa'appear to bo lean toxic to birdo than DDT. No information at all is available about the toxicity of organoohlorinos to seals but oven the most heavily contaminated anion Is studied , those from Eacit Anglia which contained 350-520 p.p.m. PCB, 30-3b p*p.m. DDT and 0.8-1.0 p.p.m. dioldrin in their blubber, did not appear to bo Buffering from uny symptoms that oould be ascribed to poisoning. The Ministry of Agriouiture, Fisheries and Food is currently carrying out a monitoring programme to determine the level of organochlorino com pounds in marine organisms and fish in the South-west. So far no exceptionally high levels have boon reported. - Other contaminants Other tissue samples from the Corninh seals wore analysed for traces of the heavy metals, arsenic, lead and mercury* The results, together with theme from the control sample of seals from the second colony are set out in Table III. The levels recorded are of the same order as has been recorded from similar organs from other mammals, though the mercury values appear higher, but there are no data for normal levels in seals. Besides the three elements listed in the table, a qualitative oc. n wan made for other possible toxic elements, but nothing exceptional wan detected. It had been suggested that the . MOD research e'Jtablichmont at Nancokuke, on the cliffs above Fortreath, might be the source of poisonous effluents, but all effluent from the laboratories nt Nancekuke is chemi cally treated to render it innocuous, and it is hold in tanks prior to discharge into the sea. Tho effluent is monitored both chemically and biol ogically. using marine organisms, before it is discharged. The suggestion is thus quite unfounded. ."What," asked one national newspaper, "is the nystoriouc red froth in the son beneath Nanookuko?" These red waters, noon be neat It Ilancekukn, at Godrony and elsewhere on the north Cornish coast, are caused by water running from the adits of the tin mines after rain. The phenomenon in well known to Corniohmcn and the Red River, which discharges into Ct, Ives Bay about n milo south of Godrovy Point, hnu roceivml its name from this. GSW 038139 STLCOPCB4021963 6 Reports of shoals of dead fish were circulated* These all appear to re1-ite t.o a shoal of young pilchard, found ashore jui.it to thw wool of Pendent by the keeper of the Poirione light--house on 2p October. These fiuh were examined by the District Inspector of Fisheries at Nowlyn, who sent npecimens to the MAFF laboratory at Burnham-on-Crouch, These were analysed for organochlorino compound<, including PCBb, but no significant onne-ntrations were found. It won concluded that this shoal had stranded and subsequently dried out. A report of undersized pollack being caught suffering from lesions described as 'burns', both internal and external, has also boen widely circu lated. The Inspector of Fisheries could not substantiate thia report and no upecimena wore found. Cod and other gadoid fishes like pollack are not infrequently found suffering from ulcerative lesions. In the oouree of the whole seal investigation only three deed sea birds were found, and although birds were not especially looked for, this seems a very low figure for the time of the year. The lack of reports of dead bird*: in the urea suggests there was no gross environmental pollution. Later observations at sea To check whether the mortality at Cornwall in 1969 approached totality, a fishing vessel was chartered on 11 Deoombar to look for surviving pups at known breeding localities (Figure 2) . The Carreck rocks, about 3 miles west of St. Ives, were first visited. I This in a regular hauling plaoe for Groy seals in the summer, but i3 not a breeding site. No seals, either adult or pup, were seen at the Carracko but a very heavy ground swell which broke over the landing places would have [aide it impossible for the seals to haul out. At the eastern limit of St, Ives Bay a young seal wan seen in the water about 100 yards to the north of Fishing Covej although stained with fuel-oil and rather thin about the neck it wao not obviously sick. Another young seal wus seen swimming vigorously in the surf to the west of Hell's Louth. At Crane Island a young seal was oenn close to the rockn, and another wait seen off Samphire Island and two more sightings were made at Ralph's Cupboard. It is possible that these were of the same animal. Another young Beal was seen just to the west of Gull Rook* At Gull Rock the tide forms an eddy where flotsam and the bodies of dead animalB accumulate, according to fishermen with local knowledge. Wo dead seals were seen here, but two oiled guillemots were picked out of the sea, t- The sighting of six or more, probably seven, young seals off the coast between Godrevy Point and Portreath indicates a fair survival of pups,*on the basis of summer sightings cf adults. Only one of the animals neon (the first sighted) did not appear to be in a perfectly healthy condition, but Borne fur'ihor mortality of young might be expeoted in the courses of the winter. No adult seals were seen during the trip} they were probably lying up in the oaves. OSw 038140 STLCOPCB4021964 9. l)i nctiBCii'on The primary cause of death of tho seal pupo found on the Cornish coast wao otarvat ion, thought to have boon caused hy the pups becoming cepnrnted from their mothers before normal woaning time. Tlio lactation parted in Grey souls is Very short, lasting Icon than 3 weeks. The mother then deserts her pup which fasts and Jones weight, before beginn ing to fend for itoolf. While it sucklcytho pup pulu on weight at an astonishing rate, ao muoh an 5.1 lbn/day being recorded (Coulnon A. Ilickling, ]u64) though probably aroxmd 3~4 lba/dny is more unual. The link between the pup ;md itn mother, its only source of food for the firnt threo weeks of its life, is a delicate one and should it be broken early the pup's chances of uurvival aro greatly decreased. It is believed that a pup which lias not readied a weight of around 65 lbs by its last milk feed is unlikely to survive the. winter following its birth. Cow senls are known to lose contact with their pups as a result of bad weather or disturbance through crowding effects or human interference. Crowding does not necessarily involve large numbers of seals; even a small number of seals in a oonfined space may constitute a orowd and disturbance to normal behaviour may follow, 00 that mortality through cows losing contact with their offspring is by far the commonest cause of pup death on Grey seal breeding grounds. Starveling pups wander about trying to feed indiscriminately from cowo, or even bulls and other pups, and are frequently savagely bitten. Infection of these wounds may occur as the pup's condition falls and eventually death may result through septicaemia. The localities on the North Cornish coast where seals are found are all exposed to northerly or westerly weather and most, if not all, the pups pro duced* in tliis area are born in the noa-oaves. Although the caves offer some protection from the weather, the space inside may be limited, particularly ut high tide, and crowding of the type mentioned above may occur when oven only half a dozen seals use a oave. A pup which strays outside its cave mny well have great difficulty in finding its way back again, particularly if the entrance to the cavo is beneath the water. It is probably the lack of good breeding sites whioh has limited tho Grey soal population in Cornwall. Grey seals occur most abundantly where the breeding fomales have access to sheltered beaches or low grosnlands behind a beach. Dy far tiie largest concentration of Grey seals in tho South-^rent in that centered on tho tip of Pembrokeshire, from Strumble Head to CaJdey Island* This area, together with part of the Cardiganshire coast, supports a population of about 300 pups, of which rather more than half are born on the islands of Ramsey and Skomer. About 200 Grey seals live on the Scilly loleo, mainly on the rocky islets to the west of tho inhabited islands and about 60 pups are produced each year. The numbers inhabiting Cornwall arc less certain. The seals are considerably more dispersed than at either the Gcillies or Pembroke and it seems likely that their numbers are added to in the summer by animals from the Pembrokeshire colonies* However, a figure of 2O0-?J)0 seals for the Cornish ooaut from Hartland Point round Land's End to thy Lizard seems reason able. Such a population would produce about 60-711 pups ouch year. DSW 038141 STLCOPCB4021965 10 Am it wun oonc)udcOL that about <10 pupa were reliably reported il<-id, ,-ind th"rn were probably bo.v> dead animoln which were not found (though it in thought that I,he;<t ware vary few) thin wouid represent a high mortality if nil the pupa (Mm.-* from l bo Corninh stock* - Grey sea In are 1 onft-lived nnimals, life spans of up to /JO yearn l^ing recorded. They linve few predators other than man and the avlult mortality rata, in ilia nhnntme of human interference, in thus very low, High Juvenile mortality r.tlrn, on the other hand, are the rule at Grey Deal breeding colonies. On the basis of existing life table dutu (Hewer 19^*4) it h/tu been am'unmd that on average f>0/> of ull pups die in thoir first yeur, montly noon after birth and weaning. Thoro io, of course, year to year variation and populations breedin/; at the foot of cliffs are very liable to total mortality of the pups in bad weather. A spell of heavy westerly weather is believed to havo killed nearly all the pupn born at a breeding site undor the cliffB of Honan Hill in Shetland in l^?. In Cornwall, seals are very little, if at all, molested by man. Killer whales, virtually the only seal predator in English waters, uro rarely Dean off Cornish coasts. As the Cornish Beal stocks do not show a rate of increase comparable to that observed in the pact quarter-century at other Grey seal oolonion at, for example, the Fame Inlands or the Orkneys, it is concluded that the juvenile mortality rotes in Cornwall must,.on average, be high, The prob,-itilo reason for this is the laok of suitable breeding sites on theinhospitable . Cornish coast. There is a possibility that not all the pups found dead originated from Cornwall, and the much larger Pembrokeshire population seems a likely source. Hiny young seals in Pembrokeshire were marked between 1$^? and 196? by the Went Wales Naturalists* Trust and of the 62 marked animals recovered outside the marking urea 20 have been recovered on the South-west Peninsula: one from the Hcilly Isles, 15 from Cornwall and 4 from Devon, Of the ?5 animals marked in 1969 one lias alroady been recovered from Cornwall, Table IV shows the incidence of winds of over 20 knots (corresponding to slightly more than Force 6 on the Beaufort scale) as recorded at Hilford Haven anti Hi, Mawgan in September, October and November 19^9* Hinds of thin speed could create sea conditions bad enough to cause some pupH in unfavourable aituations to booomo oeparated from their mothers, j Between ^ ami 9 November strong winde blew from between west and north (Table V) with opeeds of up to 41 knots. All but 7 of the 40 reports of dead and dying pups follow this period of bad weather, 110 it mmin likely that Borne of the animalo reported could havo been driven by the wind from Pembrokeshire to the Cornish coast* i* It may be noted boro tint thero was no similar reported mortality of scale from the Pembrokenhire ooust. Only two sickly pups had been noted at halo-Fort Field Centre by 10 Hocember and a representative of the U>ct Halon Naturalists* Trust considers that thore are only five reliable records of dean or dying pupn, four from around llanorbier unit one from Tenby (Fig. l). H in highly likely that other duuths ooeurr.td whicli wore not reported but it is certain tint there wan no exceptional mortality iri I'ombrokenhire. DSW 038142 STLCOPCB4021966 Summary and Conclusion About 40 reports of dead or dying Grey Beal pupn on the Cornish coast between Newrjuny and Fowey wore received in the autumn of Eleven of tlia (load seals were examined, of whioh 9 were subjects of full post-mortems, Tho cause of death wan determined to bo starvation; no evidence was found of an apidomic* Four adult seals Boon at the Lizard at the end of November had lesions on their nooks* Those looionn aro believed to bo tho result of wounds, received in fighting during the breeding season,becoming infected. Analyses of tissue samples of the dead seals show that tho Cornish seal stocks, like those from elsewhere in the British Isles, are cent fin imrl^d with organochloririo residues. The level of penticido (l)3)T and dioldrin) contamination Jo relatively low but PCB contamination in relatively high, though much lower than in seals from East Anglia* The concentration of lead ami arsenic in tho Cornish soal pups is of the same order ao that found in other mammals, Morcury levels are higher; The seal pups whioh were found doad or dying had become separated from their mothers before the normal weaning time which is about three vjeeku after birth, and had been inoufficiently developed to start feeding for them selves* The separation was probably oaused either by disturbance or bad weather* Healthy pups wero still to be found on the Corniuh coast aftor the last of tho reports was received. Some 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 is concluded that the deaths were part of the normal juvenile mortality of tho seals, always likely to be high in Cornwall, and that extraneous faotors such ao epidemios or pollution, wore not involved. W. Nigel Bonner Seals Research Officer Seals Research Unit Lowentoft. DSW 038143 STLCOPCB4021967 l'nblo I Summary of poDt-niortem 1*0ports on ten Grey seal nun3 . llof.Wo. Dale examined Sex Weight Diagnosis Organisms cultured 6022 27.10.69 6007 27.10.69 7397 t 7620 19.11.69 20.11.69 7634 29.11.69 7717 3.12.69 7789 743 0.12.69 9`.12.69 7047 9.12.69 7092 9.12.69 F. lungs only t Pneumonia M. 30 lbs. Septicaemia F. 12 lbs. Starvation F. (65 lbs) Septicaemia^ so.no degree of starva tion - 25 lbs. Starvation (pneumonia) F. 22 lbs. Starvation F. 42 lbs. Asphyxia F. 22 lbs. Starvation M. 35 lbs. Starvation t U. 33 lbs. Starvation Paoturella roultocida Pasturella raultocidu Escherichia coli Escherichia coli - Pa3tcurel3a haemolyt^ca Escherichia coli Streptococci tm Escherichia coli Proteus sp Escherichia coli Streptococci - . * estimated vcight DSW 038144 STLCOPCB4021968 1 r- . - - ! Tissue Origin Fat content per cent Lirer Cornish H. Northern (well nour ished) 5.2 9.Q Conceatr ation in tissue, Fpa wet wei-sht Dieldrir IDE TIE DDT Total insecti cide orgaacchlorine K3 0.06 1.9 0.31 0.22 * 2.51 46 0.07 0.5 0,09 0.5 1.16- 3.7 Northera (starring) 7.6 Cornish 16.7 0.07 0.25 1.0 0.15 6.7 0.69 0.9 2.12 .1 6.2 3.7 11.34 160 Slubber i Northern (well nour ished ) Northern (starring) 86.2 0.38 4.7 0.66 4.4 10.14 34- 73.3 0.57 9.5 1.16 7.4 18.63 43 ___________ Table II Synopsis of concentrations of oxganochlorine compounds in seal tissue* (For full details, see Appendix). GSW 0 3 8 1 4 5 ' C o rn is h S e a l Pups TABLE III Conoton trntiona of Aroonio, Load A Mercury in Soul tionuen, i}X}>V(i!iotl u micro^rrjna jxjr (;rna:dry weight oi.` tiunHo. (Anulyi'OO hy L'-.E. Allen, Morilovvood Mooourch Station, Nature Crmoovvtmoy. (ij'Hn/H^-ovor-Sandi), Lnncr^hlro) _________________ Cuaru;ntrntlont r* h "r-y weight icoimon No. 7043 7047 7852 7620 7634 7709 (1) HG63 HG66 HO 67 HG64 HG65 Tissue Liver 11 Liver Kidney Liver n n 11 Arsonio 20 54 3 15 8 1 10 29 Lead 1 <1 1 <C 1 5 4 3 2 Mercury 5 5 13 12 6 9 7 11 Liver Kidney Liver Kidney Liver Kidney Liver Kidney Liver Kidney 17 42 <1 '1 3.5 3.5 20 <1 15 <1 2.6 4*9 3.5 2.2 0.6 1.4 4.1 2.1 4.3 1.4 1_______________ O V 3 5 6 4 5 1 6 3 3 N o rth e rn sample GSW 038146 STLCOPCB4021970 List of Figures Flfl.l. Map to ahoff distribution of reports of dead and dying seals on tho Cornish coast. Five similar reports from Pembrokeshire are also shown. Jig.2. The coast searched for young seals. DSW 038148 STLCOPCB4021972 ikfl'oroncea Coulnon J.C. & lliekling G. 1964* The breeding biology of tho Oro.y seal, HMHchoorun grypua (Fab.) on the Fame Inlands, Northumberland. J.Anim.lCcol.j^ t 405-512 Davies J.L. 1957* The geography of tho Grey seal. J.Mammal. ^9 (3) * 297-310 Howor H.lt. 19(i4 The Determination of ago, sexual maturity, longevity and a life-table in the Grey eoal (Haliohoerua arypuo). Proc. zool. Soc. Lond. 142 (4) * 593-624. Johnston D.G. & Jlidgwoy 8.H. 1969* Parasitism in some marine mammals. J. Amor, vet# med. Asqoo. 155 -* 1064-1072 Merchant I.A. & Packer R.A. 1967* Veterinary Bacteriology & Virology. Iowa State University Press. Amer. Iowa. 7fch ed. 1967* X + 752 PP- .. DSW 038149 STLCOPCB4021973 An'IJJ.'IHX Conf-cntmtioua of orgimochlorlnn eowpoundn in nonl tj.nauoo, cxpj.-rjt.iuvO no [wntc f>or mi llion, mjt we light of tiniiuo. (Aiuilyjoo by A.V. Holden, J'Veohv/ator i''i;;heri(*M L-iborutnry, Do|i;a'tmont of Agriculture & Fioherioo for Scotland, Pitlochry, Perthshire.) .. UpecJjnon iJo. Tionuo Concentration in tiooue, p.p.m. wet weight r'at Content Bieldrin DDE TDE DDT PCB per cent ( 7043 ( 7-47 ( 7 .`jV. ( I'V.'.O W Bn*, 7634 7i*09 .1 . A<10!t (1) .tno Worage r! 7043 7047 7052 Worage Liver' 11 n II <9 II II Blubber n ii 40 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 o.oa 0.25 0.9 O.15 1.8 1.3 1.2 0.57 1.0 < O.O4 1.6 < 0,02 1.0 0.02 5.1 0.04 1.9 0.31 8.7 1.1 8.1 O.69 3.2 0.27 6.7 0.69 0.4 0.1 0.0 < 0.03 < 0.04 ^ 0.04 < 0.00 0.22 4.5 5*0 1.7 3.7 17 36 77 31 43 26 90 46 173 387 118 160 HG63 HG66 HG67 Liver 11 11 10.0 9.2 7.9 Werage 9.0 HG63 HG66 6> J1G67 iVUint*,, 'Average fl* JIC64 - 1fIO!1 HG65 ^Average t HG64 H6> Blubber ti Liver II Blubber 11 >Average 84.7 87.4 86.6 86,2 7.4 7.8 7.6 00.4 67.I 73.8 0.04 0.7 0.09 0.7 5.2 0.11 0.5 0.09 0.4 0.07 0.3 0.09 0.3 3.0) 2.2) 0.07 0.5 0.09 0.5 ) 33, .7) T*3 0.37 6.0 0.06 6.5 0.58 4.9 0.65 4.1 0,20 3.3 0,46 2.6 1 44 34 oe 25 0.30 4.7 0.66 4.4 * 34 ) 0.05 0.08 0,07 0.54 O.59 0.57 0.7 1.3 1.0 10.3 0.6 9-5 0.09 0.21 O.15 1.17 1.15 1.16 0.6 1.2 0.9 7.6 7.2 7-4 3.9 ) 8.4 ) 1------- 6.2 * n 5 --- L-- 40 ) OSW 0 3 8 1 5 G STLCOPCB4021974 I '.* D S < iIT y t& 5^-0 ^rv()U.Kcvv -f''e>p>CY& cj'droA. ifi'ftCs / IV kJ Cort-w^k cnfc, five* St^fAv 'rtjcfti ^xtnvw Vov\i>'<x.f^jsU(v\' ftve o^ii'e. 3 Aev4v < DSw 038151 STLCOPCB4021975 1 IU Vf tU*"u) r- <A 1 r <4> 3 3 a /1 Lj\T) DSW 038152 v STLCOPCB4021976