Read the following passage.
The island of New Ireland is known for its incredible biodiversity. It is home to many endemic species of birds and plants. The study region has a total area of 260,000 km2260,000\text{ km}^2260,000 km2. The actual land area of the region is only 208,000 km2208,000\text{ km}^2208,000 km2, because approximately one-fifth of this region is covered by large lagoons and coastal waters.
In December 2000, forests covered 48.2% of the actual land area.
In December 2020, forests covered 35.7% of the actual land area.
Deforestation for agriculture and timber has caused habitat fragmentation and increased soil erosion, endangering local populations of endemic avian species. Researchers often use the capture-mark-recapture method to estimate the population sizes of land birds. However, this method can produce unreliable results when applied to mobile birds in very dense canopy layers.
Use the information in the passage and your own knowledge to answer the following questions.
The percentage of forest cover in this region decreased between December 2000 and December 2020. Calculate the mean loss of forest cover in km2\text{km}^2km2 per week during this time period. Show your working.
Suggest why the capture-mark-recapture method can produce unreliable results for bird populations in dense, massive rainforest canopies.
