Phil Savoie / Salt marsh hay (Spartina patens) on beach, Cape Cod National Seashore, Massachusetts, USA, August.

Phil Savoie / Salt marsh cord grass (Spartina alterniflora) on shore of Cape Cod, Massachusetts, USA, September.

Phil Savoie / Salt marsh cord grass (Spartina alterniflora) on shore of Cape Cod, with Long Point Lighthouse in the background, Massachusetts, USA, September.

Phil Savoie / Salt marsh cord grass (Spartina alterniflora) on shore of Cape Cod, with Long Point Lighthouse in the background, Massachusetts, USA, September.

Phil Savoie / Salt marsh cord grass (Spartina alterniflora) on shore of Cape Cod, Massachusetts, USA, September.

Nick Upton / Small group of Wigeon (Anas Penelope) swimming preening and dabbling in a saltmarsh creek at high tide close to a flooded stand of Common cord grass (Spartina anglica), Somerset, England, UK, December...

Nick Upton / Small group of Wigeon (Anas penelope) swimming and dabbling in a saltmarsh creek at high tide, close to a flooded stand of Common cord grass (Spartina anglica), Somerset, England, UK, December.

Nick Upton / Saltmarsh edge on the Severn estuary stabilised with flowering Spartina / Cord grass (Spartina sp.) with the second Severn crossing on the background, Somerset, UK, September.

Nick Upton / Saltmarsh edge and Common cord grass (Spartina anglica) stabilising mudflats fringing a tidal creek, Severn Estuary, Somerset, UK, March.

Nick Upton / Wigeon (Anas penelope) swimming in a tidal creek as a high tide rises to cover Spartina / Cord grass (Spartina sp.) growing on the saltmarsh fringing it, Severn Estuary, Somerset, UK, March.

Nick Upton / Wigeon (Anas penelope) flock flying low over dense stand of Spartina / Cord grass (Spartina sp.) on tidal saltmarsh, Severn estuary, Somerset, UK, March.

Nick Upton / Wigeon (Anas penelope) flock flying low over mudflats past dense stand of Spartina / Cord grass (Spartina sp.) on tidal saltmarsh, Severn estuary, Somerset, UK, March.

David Woodfall / Spartina / Cord grass (Spartina) spreading across Severn estuary (non native invasive plant) Wales, UK April 2010

David Woodfall / Spartina / Cord grass (Spartina) spreading across Severn estuary (non native invasive plant) Wales, UK April 2010

Peter Lewis / Newly born lamb (Ovis aries) on grass, Dorset.

Nick Upton / View north to East Head across Snowhill creek and saltmarshes with stands of Cord grass (Spartina sp.), near West Wittering, Chichester Harbour, Hampshire, UK. February.

Nick Upton / Cord grass (Spartina sp.) growing on estuarine saltmarshes, Snowhill creek, near West Wittering, Chichester Harbour, Hampshire, UK. February.

Doug Gimesy / Tracy Lyten, from Skylos Ecology, undertaking kayak training with female Conservation detector dog, in preparation for work to sniff (via kayak) for invasive aquatic weeds; often Common cordgrass (Spa...

Doug Gimesy / Dog handler from Skylos Ecology undertaking kayak training with female Conservation detector dog, in preparation for work to sniff (via kayak) for invasive aquatic weeds; often Common cordgrass (Spart...

Doug Gimesy / Dog handler from Skylos Ecology undertaking kayak training with female Conservation detector dog, in preparation for work to sniff (via kayak) for invasive aquatic weeds; often Common cordgrass (Spart...

Doug Gimesy / Dog handler from Skylos Ecology undertaking kayak training with female Conservation detector dog, in preparation for work to sniff (via kayak) for invasive aquatic weeds; often Common cordgrass (Spart...

Doug Gimesy / Dog handler from Skylos Ecology undertaking kayak training with female Conservation detector dog, in preparation for work to sniff (via kayak) for invasive aquatic weeds; often Common cordgrass (Spart...

Doug Gimesy / Dog handler from Skylos Ecology undertaking kayak training with female Conservation detector dog, in preparation for work to sniff (via kayak) for invasive aquatic weeds; often Common cordgrass (Spart...

Doug Gimesy / Female Conservation detector dog in training, learning how to sniff (via kayak) for invasive aquatic weeds, often Common cordgrass (Spartina anglica) found on marshes and tidal mud flats. Beaufort La...

Doug Gimesy / Female Conservation detector dog in training, learning how to sniff (via kayak) for invasive aquatic weeds, often Common cordgrass (Spartina anglica) found on marshes and tidal mud flats. Beaufort La...

Joel Sartore / Photo Ark / Cord grass barnacle (Chthamalus fragilis) on white background, Gulf Specimen Marine Lab and Aquarium.

Joel Sartore / Photo Ark / Cord grass barnacle (Chthamalus fragilis) on black background, Gulf Specimen Marine Lab and Aquarium.

Yves Lanceau / Domestic dog, black cord-haired Poodle, female, 13 years, lying on grass, France

Yves Lanceau / Domestic dog, black cord-haired Poodle, female, 13 years, lying on grass, France