By saying that there were only penguins to greet the British settlers there is stretching the truth, but then I realised that you are speaking about the Port Egmont settlement of 1765/66. It was actually a garrison of troops rather than settlers, but there were both settlers and troops with the duly constituted settlement of Port Louis/Puerto Soledad. The British and Spanish exchanged unpleasant words until the Spanish expelled the British a few years later, and then the British were allowed to return to Gran Malvina (West Falkland). The British then abandoned their garrison there in 1774. The British then ceded their claims to any islands adjacent to South America in the Nootka Sound Conventions in the 1790s in exchange for ceded Spanish claims for what was then known as Oregon Country. Britain had earlier declared her eternal right to 'Falkland's Ysland' in the singular, meaning West Falkland. This the British Foreign Office found out about in the 20th century, and they rightfully concluded that if Britain had any legal claim, it was to West Falkland alone (For more information, read "The War in the Falklands : The Full Story" by The Sunday Times of London). The British were never established on Isla Soledad (East Falkland) until the usurption of 1833. It had been a solely French, Spanish, and most recently, an Argentine settlement. The American warship the USS Lexington then sacked the settlement and deported most (but not all of the settlement). It was into this vacuum the British stumbled into in 1833, yet there were still some gauchos, settlers, and Argentine troops in Puerto Soledad. If there were only penguins there to greet the British, why was Captain Don Pinedo ordered to leave with his troops and the remaining settlers?
So in reality, the British did indeed find 'penguins' at Port Egmont in 1766, only to abandon it permanently less than a decade later. They found Argentines at Puerto Soledad in 1833, and that is from where this dispute eminates.