When the provision of public goods requires contributions from individuals with different abilities, solicitation of efficient voluntary contributions from heterogeneous individuals becomes important. Blood banks are one such public resource. Blood banks perform a challenging task in ensuring a balanced supply of blood types to provide effective blood transfusion services. This study designs a field experiment in conjunction with a blood donation campaign to examine whether making potential donors aware of their potential contribution (the net marginal product of their donation) induces efficient individual donation behaviour. During the blood donation campaigns at the university, we conducted a field experiment with two treatments: one treatment with information regarding desired donor profiles for 400 ml whole blood donations and another treatment without such information. We find that the provision of information about desired donor profiles enhances the propensity of able donors to donate, whereas the information provision tends to depress the stated intention to donate.