I am in Chuts L’Arets visiting my family who is not religious. The house has transferred ownership. My parents are no longer owners of the house. However, the new owner of the property has not yet moved onto the property. My family is in effect renting the home from the current owner/buyer. There is a birds nest in the front yard. I have questions regarding who if anyone is obligated to perform the mitzvah of Shluach HaKan. Is my father obligated even though the house has been sold? Is the current owner obligated, who does not even reside in the house? Also, my family, who as I mentioned in not religious, have expressed to me that they are uncomfortable with the idea of the mitzvah, which they see as causing unnecessary pain to the mother bird. On the other hand, I would very much like to proceed to carry out the mitzvah because I have read about the great importance and even reward of this mitzvah. I am not sure what to do.
ב"ה Shalom It is nice to see how concerned you are with the fulfillment of this unique Mitzva. It is also nice and important to see how you describe the many details and factors involved which in many cases have direct relevance to the answer to be given. In your case,however, the issue is not so complex. According to the Mishna (Chullin 138B) and it is codified in the Shulchan Aruch (yoreh De'ah 292:2) the requirement of shiluach Haken, only applies in a situation when the nest is not in his private domain but was come upon by chance in a public domain. So, in your case where the property is being rented by you, it doesn’t fall under the category of the requirement. Furthermore, according to many Rabbis, only when you actually want to take the chicks or eggs one is required to fulfill the mitzvah, but if one doesn’t want to use take the chicks or eggs it is unnecessary cruelty to animals. So, in short, in the present situation described there is no obligation of Shiluach Haken. All the best