Johann Mayrhofer veröffentlichte seine Gedichte 1824 bei der eher kleinen Verlagsbuchhandlung Friedrich Volke in Wien. Diese Veröffentlichung ist als Digitalisat in der Österreichischen Nationalbibliothek online studierbar. Das Gedicht findet sich auf Seite 42. ^1.1

Trotz intensiver Recherche ist es uns nicht gelungen, herauszufinden, wer Ulfru ist bzw. war. Michael Davidson und Henk Hillenaar deuten den Titel beispielsweise in ihrem Buch "Schubert and Mayrhofer":

"In the first stanza the identification seems to go to Ulfru the fisherman. He is the centre of the text. with his fishing gear, his wish to get a good meal out of the water and, above all, his growing disappointment. Ulfru's cunning is for naught. The fish win the match. In this context, the last line seems even rather strange; why should a fisherman enter the water? That has never been a successful technique to catch more fish. In the second stanza the poet reveals his real focus : he is on the side of the fish, identifies with them, and mocks the fisherman. He really enjoys their movements, their blithe swimming, their darting to and fro. Fish "feel what freedom is." However, the real surprise of this text is in the last stanza, where the identification with the fish assumes another dimension, in a surprisingly philosophical or symbolical fashion. Here, it seems that the poet cherishes the safety of the fish more than their freedom. They swim in "the safe waters", already mentioned in the second stanza, now contrasted with the insecurity of the earth, "beautiful" but not "safe." All the hazards of real life, "the little fish beneath their soft roof" do not know." ^1.2

Die Deutung könnte aber auch ganz anders sein. Was, wenn Ulfru die Nixe wäre, die den Fischer in das Wasser locken möchte. - Wenn Ulfru fischt, dann fischt sie nach dem Fischer. - Das erklärt zumindest die sehnsüchtige dritte Strophe, denn unter der Wasserdecke scheint das Leben schöner zu sein als an Land. Eine ähnliche Thematik wie beispielsweise im Lied "Der Fischer".

"Wie Ulfru fischt" wurde und wird gern in Zusammenhang mit dem Lied "Die Forelle" gebracht. John Reed schreibt dazu in seiner "The Schubert song companion":

"It is difficult to avoid invidious comparisons with a roughly contemporary song, Die Forelle, which it closely resembles in tone and sentiment; and both songs show Schubert's mastery in the handling of the strophic song to produce a virtual identity of words and tune. But there is something in the stolid movement of this march tune which fails to match the lighthearted tone of the verses, so that it is quite overshadowed not only by Die Forelle but also by the two fine songs which make up op. 21" ^1.3