Every donor organization what‘s to know what you have done with their funds. Therefore, reporting is an essential part of project management. Depending on the progress of the project, you have to write a progress report or a terminal report.
In order to "stay alive" as a scientist, it is also a part of reporting to make your findings available for the scientific community. These form of reporting might be…
… a poster at a scientific meeting.
… an article in a research journal
… a contribution in popular communications and extension manual
… or a thesis
Reporting to the donor organization has to follow some rules. It is important to convince the donor that you have done good and appropriate work. This might help you for further funding.