Phocidae

Crops and damage: Phocidae damage agricultural infrastructure and coastal crops such as tidal pastures or specific wetland crops. By crossing fields, they crush young plants, destroy irrigation channels, and compromise the integrity of flood defense levees, which are critical for protecting crops from saltwater intrusion and erosion.

Biology and lifecycle: The lifecycle of Phocidae is marked by seasonal breeding and molting periods that require haul-out sites. These biological needs often lead seals to congregate on land near productive coastal zones. Their high site fidelity means they repeatedly use the same areas, creating persistent pressure on agricultural infrastructure throughout the year.

Impact on agriculture: The damage is primarily mechanical and chemical. Besides the immediate destruction of crops, the excrement from large seal colonies leads to soil pollution, which alters soil chemistry and negatively affects the growth of sensitive plants. Additionally, the destabilization of riverbanks and coastal soil structure often results in long-term loss of arable land.

Protection measures: Management strategies focus on deterring seals from sensitive areas without causing them harm:

• Deployment of acoustic harassment devices to safely discourage seals from approaching land.
• Installation of robust fencing or barrier systems designed to withstand the weight of the animals and prevent inland access.
• Use of visual deterrents or strobe lights to prevent resting behavior on farmland.
• Implementation of buffer zones between the shore and crop fields to minimize interaction and prevent soil contamination.