Why don't the birds get the bracha of פְּרוּ?

Question

In the creation of the world when Hashem is creating fish and birds, the verse in Beresheit 1:22 says,"וַיְבָ֧רֶךְ אֹתָ֛ם אֱלֹהִ֖ים לֵאמֹ֑ר פְּר֣וּ וּרְב֗וּ וּמִלְא֤וּ אֶת־הַמַּ֙יִם֙ בַּיַּמִּ֔ים וְהָע֖וֹף יִ֥רֶב בָּאָֽרֶץ׃, "God blessed them, saying, “Be fertile and increase, fill the waters in the seas, and let the birds increase on the earth.” My question is, it seems that fish get the blessing of פְּר֣וּ וּרְב֗וּ but the birds only get יִ֥רֶב (from same root as וּרְבוּ), so why is that? What differentiates the birds from the fish?

Creative ideas with sources are welcomed :)

Answer 1

Interesting to note that the שיטה מקובצת כתובות דף ה עמוד א points out that the reason why the Gemara there write's that newlywed's should have relations on Thursday, is because of the ברכה של דגים was on Thursday, and the Gemara didn't pick ברכה של עופות is because of your differentiation that by the ברכה of birds it only says ורבו.

However he doesn't provide any reason why it's so. Perhaps we can explain that because fish aren't effected by the evil eye (see Berachos 20a), therefore they can multiply more aggressively then the birds, and that is why when one gets married he does so on Thursday, so that he can achieve the unique blessing of fish that besides being able to have children we want to be protected from the evil eye as well..

Answer 2

The Or HaChaim writes that the bracha was a temporary condition:

‎ויברך טעם שהוצרך ה' לברך שרץ המים מה שלא עשה כן בנבראים היוצאים מן הארץ. ועוד לו שגם בתולדות המים עצמם הטיל קנאה שלא בירך שרץ העוף. נראה כי הדבר צריך להיות כן מטעם הכרחי לפי מה שפירשנו כי מה שצוה ה' למים שישרצו אינו אלא לפי שעה ולא לאחרי כן ולקיום המין צוה ה' שיפרו וירבו שאם לא כן הרי מינם כלה, ולהיות שכפי טבע הנבראים אשר ברא ה' כח המוליד היא יסוד האש כי טבע הקור אדרבה יפסיד כח ההולדה. וצא ולמד מחכמת הטבע גם מדבריהם ז"ל (שבת קנו:) שאמר ה' לאברהם מאי דעתיך דקאי צדק וכו' דכתיב (ישעי' מא) צדק יקראהו לרגלו יעש"ד, וכפי זה הדגים אין להם מציאות כפי טבע הקבוע בנבראים להוליד, אשר על כן חזר ה' במאמרו הנכבד וברכם לאמר פירוש כוונת הברכה שברכם הוא לומר שיוכלו להוליד ולא ימנעם קרירות המים ולא יצטרכו לצאת חוץ למים להתחמם בארץ כדרך התרנגולים (ביצה ז) דספני מארעא אלא תוך המים יעשו פרי.

And He blessed: The reason that God needed to bless that which swarmed from the waters - which He did not do with the creations that came out of the earth - and that, even among those that were born of the water themselves, He brought jealousy by not blessing the swarms of birds; it appears that this must come from an unavoidable reason, [and it] is according to that which I have explained, that that which God commanded the waters to swarm (with creatures) was only for that time and not for afterwards. [Hence,] for the survival of the specie, He commanded that they be fruitful and multiply, since, [had He] not [done] this, the species would have ended.

He continues:

And given that according to nature, the reproductive facility of the creations that God created, [comes from] the element of fire; as the nature of cold - it is just the opposite - it destroys the reproductive facility. And go and learn form natural science; also from [the] words of [the Sages], of blessed memory, (Shabbat 156b) that God said to Avraham, "what is your thinking [about this], that Saturn lies etc., as it is written (Isaiah 41:2), 'who called righteousness to His feet'" (the Hebrew word, tsedek means both Saturn and righteousness); look there at their words. And according to this, fish do not have the composition that is set in nature for creatures to reproduce and so, therefore God went back with His glorious proclamation and blessed them. "Saying" the explanation [of which] is that the intention of the blessing with which He blessed them is to say that they would be able to reproduce, and that the coldness of the water would not prevent them [from doing so]; and that they would not need to go out of the water to become warmed by the earth, like the chickens (Beitzah 7a) that are [sometimes] fertilized by the ground, but rather they would give off their fruit in the water.

His alchemical idea seems to be that reproduction is inherently linked to fire, and he cites Shabbat 156b to prove the idea of inherent capacities linked to the mazal. Because of the inherent nature of water, the fish needed a boost.

Water puts a “damper” on things, and when things start to “heat up,” love is around the corner, according to the Or HaChaim.

Yasher koach!

Answer 3

Maybe it has to do with the mitzvah of sending mother bird away Devarim 22:6-7, also Chinukh Mitzvah 545? The point is that the little chicks are called גוזלים, from the root גזל - stealing, because birds steal grain and berries from people's fields and gardens (I think also someone says it, but I cannot find a source). By the way it is related to the fact, why kosher birds need to have gizzard that's peeled by hand (Chulin 59a). The gizzard's lining is the place where the stolen grains and berries get digested. In other words, increasing the number of birds increases gezel.