Most fishery managers don't realise there are two subspecies of Great Cormorant in the UK. The Continental form (P. c. sinensis) colonised inland waters in 1981 and has been the primary driver of predation pressure on stillwater fisheries ever since. The Atlantic form (P. c. carbo) is largely coastal and has been part of our native fauna for centuries.
When you apply for an A06 licence, Natural England considers the broader population context. Demonstrating awareness of subspecies distribution, seasonal patterns, and local population dynamics strengthens your application significantly.
The Only Reliable ID Method
Forget size, plumage, and head colour — the gular pouch angle is the single reliable character. We explain exactly how to assess it in the field, with annotated photographs and the scientific diagram from Grøndahl & Johnsen (2024).
UK Population Data
From zero inland pairs in 1980 to 2,362 by 2012. Pan-European census data showing sinensis outnumbers carbo 4.5:1. Breeding, migration, and wintering patterns mapped.
Seasonal Patterns
When continental migrants arrive, when predation pressure peaks, and how feeding behaviour differs between the subspecies — including dietary research on over 1,400 birds.
A06 Licence Relevance
How subspecies knowledge strengthens all three Natural England tests: population context, satisfactory alternatives, and population-level impact.
AI-Verified Evidence
How Hydroscape's Hydro-Vision AI™ captures subspecies-relevant data automatically from your sighting photographs, building the evidence base your application needs.
Quick Reference Card
A cut-out field reference table comparing carbo vs sinensis across all key characters. Photograph it for use at the waterside.
Real cormorant sightings submitted through the Hydroscape platform, verified by Hydro-Vision AI™
Images from Hydroscape's AI-verified sighting database — North Lanarkshire, Bath & NE Somerset, Cumberland, Kent
Download the Full Guide
10 sections covering identification, population data, seasonal patterns, field methods, A06 relevance, and a quick reference card. Fully illustrated with photographs from our own database.
Download Free PDF
Every sighting strengthens the national evidence base.
No Data = No Licence.