Signs of Otters on our Lake – Carp and the Necrobiome

Our Rewilding Lead, Laura Fairs, shares how carp came to be in our lake, their threat to biodiversity and the ethical issue of removing the non-native species.

Many years ago, the community at Embercombe had the intention of being self-sufficient, growing food and rearing livestock so that people could learn to nurture a close relationship with their food and learn land-based skills. During this time, carp were introduced into the lake as a source of food and nourishment that had low food miles and known provenance. Embercombe has since changed its relationship with the land from permaculture and food production to a rewilding approach whilst keeping in aligned with its vision of a flourishing world for all species. As a result, the community no longer fish from the lake.

Carp are species non-native to the UK. Introduced in the 13th or 14th century as they were popular with anglers in fishing lakes. The carp population at Embercombe has grown large in size and in number as they’ve been left unchecked. They are an omnivorous species, feeding on almost anything they can find; smaller fish, aquatic insects, crustaceans, molluscs, fish eggs, frogspawn, tadpoles… And they hoover up aquatic plants and seeds from the lakebed. The large carp population is harming our lake’s biodiversity as many of the aquatic invertebrates and amphibians can not reach maturity before being eaten. They also stir up the sediment on the bottom of the lake, making the water turbid and murky, preventing light from reaching down into the water – something the plants need to thrive.

Every so often, we come across the awesome/gruesome sight of a headless carp with its scales scattered across the lakeside. We’ve had members of the community spot the mysterious culprit. We believe this is the work of the elusive otter! A captivating species that is rarely seen by most people nowadays.

Here at Embercombe, we’ve been discussing the ethical issue of removing carp from the lake as part of our rewilding vision and asking ourselves, how can we do this in the most natural and respectful way? One of our leading ideas is to replicate the otter attack, leaving the remains of the nutrient-rich carp to cycle back into the land and provide a vital component of our missing necrobiome – the community associated with the decomposition of animal remains. In the absence of a regular predator, can we humans act as a proxy predator but leave the carcass for other species to use as part of their lifecycle?

We will also work to make our habitats at Embercombe as hospitable as possible for any otters in our area so they can, in turn, take over the role of the apex predator in this relationship. Naturally foraging for the fish, feeding their offspring and increasing the otter population. Unfortunately, we can not ensure the rest of the watercourse will be habitable for them to move freely across our landscape. Our work with the Devon Wildland (link to previous blog) also aims to support an unbroken landscape of wildlife-friendly space where species can move freely, without barriers or persecution.

We’ve upcoming plans to install camera traps to try and spot an otter, and we’re really excited to share our findings with you all!