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DINOSAUR TRACKS FROM DORSET:A TWENTY-FIVE YEAR RETROSPECTIVEby Paul C. EnsomEnsom, P.C. 2006. Dinosaur tracks from Dorset: A twenty-five year retrospective. TheGeological Curator 8(5): 227-241.The practicalities of and issues connected with the collection of dinosaur tracks areconsidered in the light of the writers experience while Assistant Curator at the DorsetCounty Museum from 1978-1989, and subsequently. A number of short case histories aregiven.Paul C. Ensom, Holly Tree House, Croquet Gardens, Wivenhoe, Essex. CO7 9PQ, UK;e-mail: P.Ensom@pensom.fsnet.co.uk. Received 5th July 2005.IntroductionThis article is based on a talk, ‘Dinosaur tracks fromDorset (A twenty year retrospective)’, given at theGCG Seminar meeting held at the Yorkshire Museumon December 4 th 2000. My brief was to review myexperience of dinosaur tracks in Dorset and the impactthey had on both the Dorset County Museum(DORCM), and, by extrapolation, could have onother museums. The seminar was divided into twoparts. Firstly I offered a cautionary introduction undersix headings which looked at how such material hadbeen collected and the impact such specimens mayhave on the recipient institution, before giving ‘Atwenty year retrospective’ of my Dorset experienceswith dinosaur, and other, tracks. This article broadlyfollows the same format, with the addition of sectionsconsidering why dinosaur tracks are important andwhy we should consider their collection. In view ofthe lapse of over five years since the GCG seminar, Ihave expanded the retrospective’s time-span to 25years.Catalogue numbers (Cat. No.) given in the text arethose used by me (Ensom 1995a) when I reviewed themajority of Purbeck Limestone Group trackdiscoveries, published and unpublished, and provideda comprehensive indexed catalogue of them. Theindexes covered stratigraphy, locations, persons,repositories/institutions, palaeontology, and others –which included load-casts and water-hole.The importance of dinosaur tracksBefore considering the practicalities of collectingdinosaur trackways, why are dinosaur tracks of suchinterest? Trackways (two or more tracks) or an in situtrack (an individual print) provide unequivocalevidence for the presence of a dinosaur at that localitywhen the sediments had recently been laid down.Dinosaur bones found in sedimentary rocks may bederived from older strata or be parts of ‘recentlydead’ animals washed down by a river. Completecarcasses may have drifted down a river and out tosea, before sinking to the sea-floor and being buriedby sediment. The presence of the bones and even skinof scelidosaurs in the marine shales and clays of theLower Lias of west Dorset is a good example of adinosaur being found in a fully marine environment(Norman 1985). Tracks may be made in shallowwater and there are well documented examples ofswimming traces (Whyte and Romano 2001), whichat least indicate the close proximity of land. Dinosaurtracks may provide useful information about theenvironments in which they were made and the stateof sediments when walked on (Ensom 1995a, Romanoand Whyte 2003). Dinosaur tracks have the potentialto provide valuable information on the distribution,social groupings, behaviour, biomechanics andlocomotion of these extinct creatures (Alexander1989, Thulborn 1990, Romano and Whyte 2003).Why collect them?Any museum confronted with the opportunity tocollect dinosaur tracks should be asking somesearching questions before doing so. Some of theseconsiderations are raised under the ‘Practicalities ofcollection’ heading below. Fundamentally, before adecision to collect them is made, thought must begiven as to whether the trackways or individual trackwould be better left where they are. Do they representsomething new, either ichnotaxonomically-227-
(preservational considerations are likely to be relevantin this context) or stratigraphically? Do they havedisplay potential? While in Dorset, I was responsiblefor publishing a number of short accounts recordingthe discovery of dinosaur tracks which were recordedin situ and not collected (Ensom 1995a, b).In working quarries, there will almost certainly befinancial reasons why the destruction of trackwayswill be inevitable if they are not collected. Either thator they will be broken up and sold off piecemeal tothe curious. The collection of pavements of any sizewill cause some disruption to an industry which relieson extraction taking place primarily during the ‘dry’summer season, so that stone can dry and ‘cure’before the winter months. Delay to stone extractionhas an economic impact; the heavy plant, hired to digthe stone, once on site costs money regardless ofwhether or not it is working! Exceptionally (see‘Kevin Keates Quarry’, below) there may beagreement to sacrifice reserves of valuable stone inorder to leave a pavement in situ. Coastal sections arelikely to be under constant attack from the sea andwith the reality of rising sea levels this will becomeincreasingly so. Can representative prints or sectionsof a track be lifted and preserved which allow therelationship of the different tracks to be studied,especially if the track is new to science or showsfeatures not previously observed? Collectingrepresentative tracks of a large quadupedal dinosaurwill be a significant challenge in itself! The case forpreserving large parts of multiple trackway sites (see‘Townsend Road’ and ‘Sunnydown Farm Quarry’,below) may be compelling.Practicalities of collectionAny prospective collector would do well to rememberthat there are not many geological specimens whichcome bigger and heavier than dinosaur tracks. Theyshould consider very carefully a number of issuesbefore embarking on their collection. They includethe following:• The ownership of the site. Permission toinvestigate a site, then to excavate and collect,must be obtained from the landowner(s). Issuesof ownership and where any specimens collectedwill go should be addressed as soon as practicable,unless the exercise is seen as purely an opportunityto record and publish the occurrence. The owner’sagreement that the information will be publishedand/or placed in a public archive should beobtained.• Legislation and planning. Not only shouldpermission from the owners of a site be obtained,-228-but consideration should also be given to whetherlocal or national laws might be infringed, e.g.,National Park and/or National Trust Byelaws,and restrictions pertaining to a site’s designationas an SSSI. Consulting representatives of EnglishNature or their equivalents in Wales and Scotland(both countries have trackway sites), or the localMinerals Officer with the County or DistrictCouncils, may be informative. Large-scaleexcavations may require planning permission ifsuch a consent does not already cover the site.• The accessibility of the site. Access to remote orinaccessible sites can present huge problems,both during the excavation phase and, critically,during the recovery operation. While quarrieswill normally have reasonable vehicular access,there may be restrictions on the number of vehiclemovements which can take place each day. Coastallocations usually present most of the difficultiesconfronted at the worst inland venue, with theadditional hazards of rocky shores, and tideswhich can inundate sites and cut-off the unwary.Access by sea could be an advantage. Analternative is collection by helicopter (Figure 1).Access rights will at least need to be checked andmay need to be cleared with the owners of adjacentland or land crossed to reach the site.• Manpower and equipment. Trackway sites willoften require several very fit and suitably equippedindividuals with appropriate skills in handlingheavy blocks of stone with weights up to, andsometimes more than, a tonne. Access toequipment to lift and position such material maybe possible through contacts in the local quarryingindustry (see also ‘Risk assessment’, below).Angle grinders were used at a site in 1981 (Figure2) and can still be hired, though I understand thatfitting the blade is a process for which the usershould have received training. These are highlydangerous machines, but very effective forisolating and thinning slabs of rock with trackwayspreserved.• Costs. Recovering a trackway site will ofteninvolve a considerable amount of time. If salariedstaff are involved or temporary labour is beingcontracted, salary costs with attendant overheadsshould be taken into account. Travel to and fromthe site will also need to be factored in along withsubsistence costs, and, possibly, overnightaccommodation. In the absence of friendly supportfrom local industry, the full costs of equipmenthire and transport will also have to be taken intoaccount. In the case of the Sunnydown Farmexcavation in 1986/87, the Dorset Natural History
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Page 66 and 67: Figure 8. This Early Cretaceous tra

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