Winter 2005

How many plants are there on the Sefton Coast?

Philip H. Smith

The Sefton coast is renowned for its biodiversity, particularly wild flowers. But how many different plants are found here? With the completion in 2005 of an “Inventory of Vascular Plants for the Sefton Coast” we can now make a pretty good stab at answering that question. All the reliably identifi ed higher plants (flowering plants and ferns) in the Sefton Coast Partnership area from Bootle to Crossens are included, together with a separate list for the sand-dunes. The data are summarised in Table 1.

A species is a group of related organisms that share a more or less distinctive form and are capable of interbreeding
Sub-species: a subdivision of a species; usually occurs because of a isolation within a species, though not suffi ciently different to be classed as a new species.
Hybrid: an individual resulting from a cross between different species or sub species.
A grand total of 1173 different species, sub-species and hybrids has been recorded, 1054 of which occur in the sand-dune system. Aliens (non-native plants or introduced natives) account for about 37% of the coast’s flora, this proportion having increased in recent years due to garden escapes. However, this is not a particularly high figure, as South Lancashire as a whole has 50% alien plants.

A recent publication gives the total number of vascular plants in the South Lancashire vice-county (old Lancashire between the Mersey and the Ribble) as 2096. So the Sefton Coast supports an amazing 56% of the entire vice-county flora.

Image of a Bee Orchid copyright Phil Smith Also remarkable is the number of “notable” plants found here. There are 13 Nationally Rare, 20 Nationally Scarce and 133 Species of Conservation Importance in North West England. This is equivalent to 35% of all the notable plants in Cheshire, Cumbria, Greater Manchester, Lancashire and Merseyside put together!

Since the beginning of recording on the coast in the 19th century, only 39 vascular plants are thought to have become extinct and some of these may yet turn up again. Thus, nine species thought to have been lost have been rediscovered since 1999.

Image of hedge bindweed copyright Phil Smith The results of this exercise confi rm the long-held belief that the Sefton Coast has the richest fl ora of any comparably sized area in northern England. This is an important fi nding because plants form the base of food chains supporting a huge range of invertebrates and other animals, from slugs to birds. Also, knowing how many plants we have is essential base-line information which can be used to judge the effectiveness of conservation in the future.

Table 1. Sefton Coast Sand Dunes
Total no. of plants 1173 1054
No. introduced 433 348
% introduced 36.9 33.0
Certainly or possibly extinct 39 36
Nationally Rare 13 13
Nationally Scarce 20 17
Species of Conservation Importance 133 128