“It is a wrong assumption that due to an increase in population the world becomes overburdened and therefore there are wars and other extinction processes. The planet is never overburdened. The heaviest mountains and oceans on the surface of the earth hold more living entities than there are human beings, and they are not overburdened. If a count were taken of all the living beings on the surface of the earth, certainly it would be found that the number of humans is not even five percent of the total number of living beings. If the birthrate of human beings is increasing, then the birthrate of other living beings is rising proportionately. The birthrate of lower animals–beasts, aquatics, birds, etc.–is far greater than that of human beings. There is sufficient arrangement for food for all the living beings all over the earth by the order of the Supreme Lord, and He can provide more and more if there is actually a disproportionate increase of living beings.
Therefore, there is no question of an increase in population causing a burden. The earth became overburdened due to dharma-glani, or irregular discharge of the Lord’s desire. The Lord appeared on the earth to curb the increase in miscreants and not the increase in population, as is wrongly put forward by the mundane economist. When Lord Krishna appeared, there had been a sufficient increase in culprits who had violated the desire of the Lord. The material creation is meant for fulfilling the desire of the Lord, and His desire is that the conditioned souls who are unsuited to enter into the kingdom of God have a chance to improve their conditions for entering. The entire process of cosmic arrangement is meant just to give a chance to the conditioned souls to enter the kingdom of God, and there is an adequate arrangement for their support by the nature of the Lord.
Therefore, although there may be a great increase in population on the surface of the earth, if the people are exactly in line with God consciousness and are not offenders, such a burden on the earth is a source of pleasure for her. There are two kinds of burdens. There is the burden of the beast and the burden of love. The burden of the beast is unbearable, but the burden of love is a source of pleasure. Srila Visvanatha Cakravarti explains the burden of love very practically. He says that the burden of the husband on the young wife, the burden of the child on the lap of the mother, and the burden of wealth on the businessman, although actually burdens from the viewpoint of weight, are sources of pleasure, and in the absence of such burdensome objects, one may feel the burden of separation, which is heavier to bear than the actual burden of love. When Lord Krishna referred to the burden of the Yadu dynasty on the earth, He referred to something different than the burden of the beast. The large numbers of family members born of Lord Krishna counted to some millions and were certainly a great increase in the population of the earth, but because all of them were expansions of the Lord Himself by His transcendental plenary expansions, they were a source of great pleasure for the earth. When the Lord referred to them in connection with the burden on the earth, He had in mind their imminent disappearance from the earth. All the members of the family of Lord Krishna were incarnations of different demigods, and they were to disappear from the surface of the earth along with the Lord. When He referred to the unbearable heaviness on the earth in connection with the Yadu dynasty, He was indicating to the burden of their separation. Srila Jiva Gosvami confirms this inference”
Source: A.C. Bhaktivedanta Swami Prabhupada (2014 edition), “Srimad Bhagavatam”, Third Canto, Chapter 03 – Text 14