Fishguard Fossil Hunting

Fishguard combines rugged volcanic scenery with reports of graptolites and trace fossils in occasional shale. This guide focuses on Pwll Landdu, the small cove east of Fishguard Fort; the fossil photographs illustrate the reported material, although their exact collecting bed has not been established.

FIND FREQUENCY: ♦ – Fossils have been reported in scarce shale; a productive bed at Pwll Landdu is not confirmed.
CHILDREN: ♦♦ – Close supervision is needed on the coast path. The difficult shore is unsuitable for a family collecting trip.
ACCESS: ♦♦♦ – The fort and coast path are accessible from the road. Shore access is a separate, difficult undertaking; see Access Rights.
TYPE: Cliff-top observation, with historical reports of fossils in loose foreshore shale.

DIRECTIONS

♦ From Lower Town, take the A487 towards Newport to the small Fishguard Fort car park above the harbour, at grid reference SM962375.
♦ Follow the path towards the fort, then the waymarked coast path eastwards towards the cliffs above Pwll Landdu. The path to the fort becomes steep below the viewpoint.
♦ These directions describe the public coast path. Do not use the old steep shore descent or attempt a foreshore shortcut from Fishguard beach without confirming a suitable route locally.

FOSSIL HUNTING

The material to look for in the Fishguard photographs is fine-grained, flaky shale, rather than the hard igneous rock which dominates the cliffs. The collecting account describes shale as uncommon, with graptolites and trace fossils on some surfaces. This is useful guidance to the kind of material reported, but it does not establish a currently productive bed at Pwll Landdu or guarantee finds on a visit.

Graptolites were colonies of small animals. Their fossils commonly resemble dark pencil strokes or thin, shiny lines on a bedding surface; a hand lens may reveal the closely spaced cups along a branch. A two-branched, tuning-fork outline is a useful recognition clue, but species identification needs more than that outline. The name Didymograptus murchisoni was applied to the illustrated Fishguard material in the collecting account; it is retained here as a reported identification, rather than a newly verified determination of these specimens.

For an observation visit, photograph any naturally exposed markings with a scale and take a wider photograph showing their setting. Examine existing loose surfaces only where access is safe and permitted. Delicate shale can break into thin flakes, so an apparently blank reverse or a broken counterpart may still carry part of the same fossil. Record whether a specimen was loose or attached to a bed; a loose fragment alone cannot establish a formation or fossil zone.

Trace fossils are records of an animal’s activity rather than its body. The guide’s reports of traces do not provide enough information for a reliable named ichnospecies. Do not label every line as a burrow or every forked marking as a graptolite: cleavage, fractures and mineral markings need to be distinguished from a repeated biological structure. Clear close-up and context photographs are more useful than a confident but unsupported label.

There are scientifically documented graptolite sites around Fishguard Old Harbour, including a separate shale occurrence south of Castle Point. Those records help explain why Fishguard is important to geologists, but they must not be treated as a fossil list for Pwll Landdu. The precise collection points of the specimens pictured below remain unconfirmed.

Significant fossil discoveries, collections and geological research around Fishguard, with the scope of the Pwll Landdu records.

2010–2012 – New geological map and district explanation
A revised geological map of the Fishguard district was published in 2010, followed by its geological explanation in 2012. This provides the regional framework for the volcanic and sedimentary coastline around Fishguard, including the area of Pwll Landdu. It does not identify the bed from which the specimens illustrated in this guide were collected.

GEOLOGY

Pwll Landdu lies on the rugged eastern side of Fishguard Bay. The National Park’s coastal assessment describes this shore as an Ordovician landscape of sedimentary mudstones and sandstones alongside more resistant volcanic rocks and intrusions. Differences in resistance help produce the irregular headlands, small coves and rocky shore. Modern beach shingle is a loose deposit at the foot of the cliffs, not a separate bed within the ancient volcanic succession.

The regional Fishguard Volcanic Group includes rhyolitic and dacitic lavas, basaltic pillow lavas, breccias, tuffs and sediment deposited among volcanic material. Tuff is made from volcanic ash; shale is a sedimentary rock formed from fine mud. This distinction matters to fossil hunters because a dark, fine-grained rock is not automatically fossiliferous shale. The occasional soft shale described in the collecting account should not be assigned to a named formation merely from its appearance.

Nearby Old Harbour exposures are important because graptolites in sedimentary rocks below and above the volcanics help constrain the timing of eruption. They are separate scientific localities, rather than a measured section through Pwll Landdu. The cove’s detailed bed sequence and the horizon of the illustrated fossils have not been securely established, so the framework below distinguishes regional geology from the observations associated with this guide.

Pwll Landdu observations, the regional volcanic group and separate Old Harbour reference horizons.

Scope of this framework
The guide’s cove is Pwll Landdu, east of Fishguard Fort. The following account separates that shore from the independently documented Old Harbour fossil localities. It is not a bed-by-bed log of the cove.

Pwll Landdu: exposed and loose material
The shore lies within a coastal tract of Ordovician sedimentary and igneous rocks. The photographs show hard, jointed cliff rock and beach shingle; the collecting account also describes scarce, flaky shale with fossil markings. The photographs and account do not establish a formal formation, member, measured thickness or graptolite zone for that shale. Loose beach material must be kept distinct from an identified bed in place.

FISHGUARD VOLCANIC GROUP — REGIONAL CONTEXT

The group is assigned to the Abereiddian Stage in the British Ordovician scheme. Its regional assemblage includes rhyolitic and dacitic lavas, basaltic pillow lavas, volcanic breccias, acid tuffs and intervening volcaniclastic sediment. These describe the group across its outcrop, not a claim that every rock type can be seen in this cove. The regional figure of approximately 1,800 m is not a thickness measured at Pwll Landdu.

Subdivisions and boundaries
Around Goodwick and Fishguard Harbour, the volcanic succession has been divided into the Porth Maen Melyn, Strumble Head and Goodwick volcanic formations. Their boundaries are not plotted here through Pwll Landdu. The detailed modern mapping distinguishes fault-controlled changes in the rocks above the group; a simplified regional boundary description cannot safely be transferred to an unidentified shale fragment.

Separate Old Harbour reference horizons
At Aber Bach and south of Lampit Bach, graptolite-bearing slate below the volcanics is referred to the artus Zone. A separate occurrence about 100 m south of Castle Point comprises roughly 10 m of fissile shale with thin tuffs and a reported murchisoni-age fauna. The published account is inconsistent about which harbour bank contains this upper occurrence; the locality descriptions must not be used as directions to Pwll Landdu or to relocate the illustrated specimens.

Fossil preservation and structural overprint
The Old Harbour account notes that the relationship between bedding and cleavage affects whether recognisable graptolites are exposed. A slab can therefore split along a surface which is not its original depositional bedding. This is a useful regional caution when interpreting thin flakes, not proof of the structural orientation of the cove’s fossil horizon.

Modern shore deposits
Beach shingle and fallen rock lie outside the formal ancient bedrock hierarchy. They can move and mix material, so neither a beach pebble nor an isolated photographed fossil provides a measured stratigraphic position. No thickness, numbered bed succession or exact fossil zone is assigned to Pwll Landdu in this guide.

References

Burt, C. E. and colleagues (2012). Geology of the Fishguard district. British Geological Survey, Sheet 210 explanation; the accompanying map was published in 2010.

British Geological Survey. Fishguard Volcanic Group, Lexicon entry FIV.

Rushton, A. W. A., Owen, A. W., Owens, R. M. and Prigmore, J. K. (2000). Abergwaun (Fishguard Old Harbour), British Cambrian to Ordovician Stratigraphy, Geological Conservation Review 18.

Pembrokeshire Coast National Park Authority. Seascape Character Assessment: Fishguard Bay East.

SAFETY

Stay on the waymarked coast path and keep back from cliff edges, undercut ground and steep grassy slopes. Strong footwear is important, particularly in wet weather. Supervise children closely and avoid exposed cliff-top walking in strong winds.

The small cove has a difficult land approach. Do not climb the cliffs, scramble down an unverified route or try to link it to another beach around a headland. Tides and waves can remove an escape route, and a falling tide does not make an unsafe descent suitable. Carry a charged phone, but do not rely on continuous mobile coverage.

EQUIPMENT

For the coast path, take walking boots, weatherproof clothing, drinking water and a map. A camera, a small scale and a hand lens are useful for recording rock textures and any fossil markings without disturbing them.

If the landowner has specifically permitted collecting at a safely accessible place, bring soft wrapping and small rigid boxes for fragile shale. Keep separate pieces supported and labelled. A hammer is not needed for a photography visit; do not break cliffs, bedrock or loose material without the appropriate permission.

CLEANING AND TREATING

The thin fossil-bearing shale described here needs very little preparation. Support each piece in a shallow box and avoid rubbing the fossil face. If a lawfully collected specimen is wet, allow it to dry slowly at room temperature rather than using heat; stop handling it if layers begin to lift.

Do not soak flaky shale, scrub a graptolite film or try to expose a fossil with acid or bleach. Photograph the specimen before any work, retain matching fragments and their labels, and seek specialist advice if it is unstable or scientifically useful. Routine varnish or glue can obscure the very details needed for identification.

IDENTIFY YOUR FINDS

FURTHER READING

BGS: Geology of the Fishguard district (2012)
BGS Lexicon: Fishguard Volcanic Group
GCR: Abergwaun, the separate Fishguard Old Harbour fossil sites
BGS: recognising graptolites
Pembrokeshire Coast National Park: Newport to Fishguard route
Pembrokeshire Coast National Park: Fishguard Bay East assessment
Pembrokeshire Coast National Park: Fishguard Fort

ACCESS RIGHTS

Use the public coast path for views of Pwll Landdu. The National Park’s coastal assessment describes the cove both as virtually inaccessible and as just accessible from the path; it does not provide a maintained, safe descent. Check locally before planning any shore visit and choose a cliff-top observation visit if a suitable route cannot be confirmed.

Seek the landowner’s permission before removing fossils or other specimens, and check current conservation restrictions and notices. A public path does not itself authorise collecting. Fishguard Fort is described by the National Park as a scheduled monument and SSSI; do not disturb its structures or rock exposures. That description should not be used to assume the precise protected boundary or collecting conditions at Pwll Landdu.

It is important to follow our ‘Code of Conduct’ when collecting fossils or visiting any site. Please also read our ‘Terms and Conditions‘

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