‘A Dictionary Of The Sussex Dialect,’ is where I got the term ‘Looker’ from back in 1999; it states:
Looker (east Sussex from Anglo Saxon to ‘look’). A shepherd or herdsman; a man employed to look after cattle in the marshes.
Lookering. The occupation of a ëlookerí in the marshes.
Below, is an additional piece I found on the web, plusother info. http://www.hunnisett.org.uk/tree/richard1748.php
“Richard Hunnisett (1748 – 1827). Richard was a ‘looker’ in the Wartling and Herstmonceux area. A Marsh Looker was someone who looked after sheep and cattle on the marshes to the south of these villages, on the Pevensy Levels and was often provided with a cottage and a small amount of land and often owned some livestock of their own. Checking the cattle is still known in the area as ‘lookering.’ Whilst it doesn’t sound very glamorous Richard apparently made a good living.”
Traditionally, many local farms would own a small area of the Pevensey Levels and in the days before the car, paid/shared men to keep a day to day watch over their livestock. Exceat Farm near Seaford for instance, then owned 47 acres of the Levels. Today, the word has come to the fore within conservation grazing circles around the country. Wildlife conservation would not be able to manage without volunteer lookers.