Well, I know this breed is nocturnal and feeds on roots... ...or possibly human effluvia.

They have gone skulking back to the railway works, whilst leaving a great pool of... ... effluvia.

11.23 The Act (Section 8) makes provision for the workplace to be "kept clean and free from effluvia from any drain, privy or other nuisance. " Section 10 of the Act provides for the maintenance of proper ventilation "to prevent injury to the health of employees.