Again from Gary’s website, Phrase Finder
An oath, expressing annoyance or surprise.
Robert Louis Stevenson used shiver my timbers several times in the original 1883 book, for example: “Well, he [Old Pew] is dead now and under hatches; but for two year before that, shiver my timbers, the man was starving!” The first appearance of the phrase in print is in Frederick Marryat’s Jacob Faithful, 1834: “I won’t thrash you Tom. Shiver my timbers if I do.”…
…One meaning of shiver, which is now largely forgotten, is ‘to break into pieces’. That meaning originated at least as early as the 14th century and is recorded in several Old English texts. …
…So, the sailor’s oath shiver my timbers, is synonymous with (if so and so happens then…) let my boat breaks into pieces. The question is whether any real sailor used the term or whether it was just a literary invention…
An oath, expressing annoyance or surprise.
How appropriate then that the Flickr photo you chose is of HMS Surprise in San Diego (I’m 99% certain)