Why would a boycott work on a country?

The country would face economic pressure because of reduced trade or growth.

Boycott is typically not buying a product for something or not doing something.

uhh idk for sure but i think it makes it difficult to pump the oil through the oil rigs

the invasive species was introduced due to commercial purpouses, as there was a demand for fur clothes and hence, a business opportunity connected to this product. actually, it was when the nutrias scaped, causing harm to the us ecosystems when they acquired the status of invasive species. in this case they have caused an environmental problem, but it could have affected also economic interests or even human health.