It is unquestionably cruel to destroy or relocate a nest containing eggs and/or fledglings. The problem is due to the fact that birds are relatively stupid. Whereas, if I moved your house a short distance from its current location, you would obviously look for it and quickly find it, birds don't work this way. If a mother bird is out looking for food, then returns to the location of the nest and finds it missing, she will not look around for it; she will simply assume that it has ceased to exist, and will leave the area.
Relocating an active nest is not an option. Birds do not possess the power of reason, if the nest disappears the parents will not go searching for it.
The Audubon Society
If there are eggs in the nest, they will die of exposure or predation; if there were fledglings in the nest, they will either be killed by predators or die a horrible, lingering death due to exposure, dehydration, or starvation.
You have said that your problem with the nest is that the chirping annoys you; this is a very minor complaint, and certainly doesn't justify killing the birds and causing significant distress to the mother. The good news is that you don't have to wait very long.
Wait until the nest is empty, or at least until the eggs have hatched and the fledglings have left the nest - it would be even better if you waited until the entire early summer breeding season has ended. This won't take very long - on average, the total time between the eggs being laid and the fledglings becoming mature enough to leave the nest is about 4-6 weeks. After the babies are grown and leave their parents and the nest, you can either destroy the nest outright or move it to a more convenient location. The important thing is that you don't disturb the nest while it still contains eggs and/or juvenile birds.
Relocating Nesting Birds
These instructions are for Starlings and House Sparrows only. All other common nesting songbirds are protected by federal law, which prohibits the moving of their nests. Before you interfere with any nest, identify the species by watching the adult birds at the nest.
What to Do?
We strongly advise the public to leave nesting birds alone and wait for the youngsters to fledge, or leave the nest, before [destroying or relocating the nest] Common birds that nest on buildings, such as House Finches, Easter Phoebes, Barn Swallows, Robins and Carolina Wrens spend about 2 weeks incubating their eggs and then 12-18 days raising their young in the nest. Waiting those 4-5 weeks for the babies to grow and fledge is the kindest way to deal with the situation.
When “waiting it out” is not possible, in the case of House Sparrows and Starlings only, it may be possible to relocate the nestlings into a temporary nest box as close as possible to the original site, to allow the parent birds to finish raising their babies. After all the birds leave the nest, the nest box should be taken down and discarded. The original nest site must be made inaccessible to other House Sparrows and Starlings, or they will nest there again.
- The Raptor Trust
There are also legal reasons to leave the nest alone - in many places, including the U.S. and Israel, it is actually a crime to tamper with active songbird nests.
As you said, the question is not a matter of Halacha, but a matter of mercy and compassion. This makes it even more clear that the best course of action would be to grin and bear it for a month, then, if necessary, you can deal with the problem so it isn't an issue in the future. The most compassionate way to prevent a recurrence of the problem would be to install a nesting box somewhere far enough away from your study that the noise won't bother you when breeding season returns.
It is worth mentioning that the sound of birds chirping isn't a bad thing - remember Solomon:
And Solomon awoke, and behold it was a dream: and behold he understood that his dream was true. He would hear a bird chirp and understand its language, a dog would bark and he would understand its language.
- Rashi on I Kings, 3:15
Things to Consider:
Note: Citation links apply to everything since the last citation link
This Mitzvah requires us to follow the Middos of Hashem with all of our capabilities. As Chazal teach, just as Hashem is a Chanun (gives something for nothing), so too, should we be a Chanun. Just as Hashem is a Rachum (he is merciful to us even if we are not deserving), so too, should we be a Rachum. Just as Hashem is a Chossid (He goes beyond Din, the letter of the law, and is kind to us), so too, should we be a Chossid…and the same holds true for all of the other Middos that are used to describe Hashem (see Micha 7:18-20 and Sefer Tomer Devorah, Chapter 1 for the Thirteen Middos of Hashem, and how we can practically apply them to our lives). This Mitzvah applies at all times, and to men and women alike.
R. Samson Raphael Hirsch, who was an eminent Torah scholar, and strictly observant of Torah law, wrote about bal tashchit with a passion and expansiveness that was, even for him, remarkable. For example, in the description of bal taschit published in his seminal book Horeb, Hirsch writes:
"And from this [the prohibition of bal tashchit] you should hear the warning of G-d: - Do not corrupt or destroy anything and apply it to your whole life and to every being which is subordinated to you, from the earth which bears them all to the garment which you have already transformed into your cover. Do not corrupt or destroy anything is the first and most general call of The Creator, which comes to you, Man, when you realize yourself as master of the earth. All round you, you perceive earth and plant and animal, already bearing your imprint from your technical human skill. They have been transformed by your human hand for your human purposes, into dwelling-place and clothing, food and instruments, and you have taken them as your property....Only if you use the things around you for wise human purposes, sanctified by the word of My Torah, only then are you a Man and have the right over them which I have given you as a Man. However, if you use them unwisely, be it the greatest or the smallest, you commit treachery against My world, you commit murder and robbery against My property, you sin against Me!"
"Therefore the sages say, he who in his wrath tears his clothes, breaks his vessels to pieces, or scatters his money, should in your eyes be as one who has worshipped idols... And in truth, there is no one nearer to idolatry than he who can disregard the fact that things are property of The Creator, and who presumes also to have the right, since he has the might, to destroy them according to his presumptuous will. He is already serving the most powerful idol in his inward self- anger, pride, above all his ego, which in its passion regards itself as the master of all things."
R. Hirsch likewise writes, in his commentary on the Torah (on Deuteronomy 20:20):
"But the prohibition of purposeless destruction of fruit trees around a besieged city is only to be taken as an example of general wastefulness. Under the concept of bal tashchit the purposeless destruction of anything at all is taken to be forbidden, so that the lo tashchit [don‘t destroy] of our text becomes the most comprehensive warning to human beings not to misuse the position which The Creator has given them as masters of the world and its matter to capricious, passionate, or merely thoughtless wasteful destruction of anything on earth. Only for wise use has The Creator laid the world at our feet when He said to Man ―subdue the world and have dominion over it".
Midrash from Kohelet (Ecclesiastes) Rabba:
"When G-d created the first man he took him and showed him all the trees of the Garden of Eden and said to him "See my works, how beautiful and praiseworthy they are. And everything that I created, I created it for you. Be careful not to spoil or destroy my world – for if you do, there will be nobody after you to repair it."
The Sefer HaChinuch:
"This is the way of the pious and elevated people; they love peace and rejoice in the good for other people, and to bring them near to God‘s way. They will not [needlessly] destroy even a mustard seed, and they are distressed at every ruination and spoilage they see. If they are able to save, they will save anything from destruction with all of their power. Not so, however, are the wicked, the brethren of destructive forces that rejoice at the destruction of the world, until they themselves become destroyed..."
The Sefer HaChinuch clearly links pious and elevated behavior with what might today be called "eco-friendly" or at least 'environmentally-responsible'. The 'wicked' he describes as acting in a way that is very destructive to the world.
R. Moshe Cordovero (1522-1570):
"One‘s mercy should extend over all creations, not to treat them disrespectfully or destroy them. For the Higher Wisdom is spread upon all creations, [including] inanimate matter, plants, live creatures and people. And for this reason, we are warned against treating food disrespectfully. Along these lines, it is befitting that just as the Higher Wisdom does not disdain any creature, and causes everything, as it is written: 'You made them all with wisdom' (Psalms 104:24), so should man‘s mercy be upon all The Creator‘s works... Along these lines, a person should not treat anything disrespectfully, for all were made with wisdom. He should not uproot a plant except where necessary, and he should not cause the death of a living creature except where necessary, in which case he should ensure them an easy death, with a checked [properly sharpened] knife, to be as merciful as possible. This is the general principle: Having compassion on every being, in order not to destroy them is dependent on wisdom."
R. Avraham Isaiah Karelitz (1878-1953), one of the leading halachic authorities of the twentieth century, writes that even those animals not normally considered beneficial to man contribute, at least subliminally, to mans existence:
"Animals are of utility to man, such as an ox for a yoke and a donkey for a burden, and they prepare food for man, milk and eggs, and from some of them we obtain wool to wear, and some of them are themselves food for people. They were created as different kinds and as many species, and the food of each is different. Some of them people do not benefit from, such as predatory animals, and snakes, and vermin, and insects; however they possess sublime necessity and benefit. Sometimes man is punished by way of them, and sometimes man learns wisdom and ethics from them. We are already used to their existence, and we feel that without them the world would be lacking, and the world is not beautiful and perfect except when there are predatory animals in it."
From these words, it appears that according to some halachic authorities, all animals are of at least potential benefit to man. Therefore, intentionally killing or damaging any animal without sufficient need may violate the prohibition of bal tashchit.
Animals – The Talmud considers the unnecessary killing of animals to be a violation of bal tashchit. For example, the Talmudic sage Rebbi refused to destroy a certain type of animal living on his property, despite the potential danger they posed, because he considered killing them to be a violation of bal tashchit.
The condition "may be of benefit" requires further clarification. One could argue that virtually everything in nature is of at least potential benefit to humans, and therefore may be included within the prohibition of bal tashchit. Indeed, a number of Jewish sources state that everything in the world exists for man's benefit.
For example, according to the Talmud:
"Rav Yehuda said, of everything that the Holy One created in His world, He did not create anything in vain. He created the snail [as a cure] for scabs, the fly [as an antidote] for hornet stings, the mosquito [as an antidote] for snakebite, snakes [as a cure] for sores, and spiders [as an antidote for the stings of] scorpions."
The Midrash brings a similar statement, as follows:
"Even things you see as superfluous in this world – like flies, fleas, and mosquitos – they are part of the greater scheme of the creation of the world, as it says [Genesis 1:31] 'And the Creator saw all that He had created, and behold it was very good'..."
Maimonides, in his Guide for the Perplexed, writes:
"The truth, it seems to me,... is that we shouldn‘t believe that all beings exist for the sake of Man, but rather that the other beings also have been intended for their own sakes, and not for the sake of something else."
[Guide for the Perplexed, 3:13]
Tza’ar Ba'alei Chaim
Rabbi Yehudah HeChassid, Sefer Chassidim, 87, translation by Rabbi Dovid Sears:
"And G-d will give you mercy, and show mercy to you" (Deuteronomy 13:18). G-d will instill in you the trait of mercy and compassion; then He will "show mercy to you." If one has mercy upon living creatures, Heaven will have mercy upon him (Shabbos 151b). However, if a person lacks mercy, there is no difference between him and a beast, which is not sensitive to the suffering of other creatures."
Talmud: Bava Metzia 85a, translation by Rabbi Dovid Sears:
"Once a calf being led to slaughter thrust its head into the skirts of Rabbi [Yehudah HaNasi]'s robe and began to bleat plaintively. "Go," he said, "for this is why you were created." Because he spoke without compassion, he was afflicted [at the hand of Heaven]."
"Then one day, his maidservant was cleaning his house and came upon some young weasels. She was about to chase them away with a broom, when Rabbi Yehudah said to her, "Let them be, for it is written: 'His tender mercies are upon all His works'" (Psalms 145:9). They said [in Heaven], "Since he is merciful, let him be treated with mercy." [Thereafter, his pain ceased.]"
The Sefer Hachinuch (596) writes:
"Among the motivations for this commandment is to accustom ourselves to delicate souls, choosing the straight path and adhering to it, and seeking mercy and kindness. Once we obtain this habit, then even toward animals, which were created to serve us, we will show concern."
And Nachmanides writes:
"The reason for refraining [from taking the eggs in the presence of the mother] is to teach us the quality of mercy, and not to act cruelty. For cruelty [toward animals then] spreads into the soul of man [and expresses itself toward people as well]."