Chemical composition and tissue energy density of the cuttlefish (Sepia apama) and its assimilation efficiency by Diomedea albatrosses.

The cuttlefish Sepia apama Gray (Mollusca: Cephalopoda) is a seasonally abundant food resource exploited annually by moulting albatrosses throughout winter and early spring in the coastal waters of New South Wales, Australia. To assess its nutritional value as albatross forage, we analysed S. apama for water, lipid protein, ash contents, energy density and amino acid composition. Because albatrosses consistently consume S. apama parts preferentially in the order of head, viscera and mantle, we analysed these sections separately, but did not identify any nutritional basis for this selective feeding behaviour. The gross energy value of S. apama bodies was 20.9 kJ/g dry mass, but their high water content (>83%; cf <70% for fish) results in a relatively low energy density of 3.53 kJ/g. This may contribute to a need to take large meals, which subsequently degrade flight performance. Protein content was typically >75% dry mass, whereas fat content was only about 1%. Albatrosses feed on many species of cephalopods and teleost fish, and we found the amino acid composition of S. apama to be comparable to a range of species within these taxa. We used S. apama exclusively in feeding trials to estimate the energy assimilation efficiency for Diomedea albatrosses. We estimated their nitrogen-corrected apparent energy assimilation efficiency for consuming this prey to be 81.82 ± 0.72% and nitrogen retention as 2.90 ± 0.11 g N kg^-1 d^-1. Although S. apama has a high water content and relatively low energy density, its protein composition is otherwise comparable to other albatross prey species. Consequently, the large size and seasonal abundance of this prey should ensure that albatrosses remain replete and adequately nourished on this forage while undergoing moult.

In praise of the everyday

The following forgotten text is flawed. It is a failure. It has many mistakes but few regrets. It was written 20 years ago and first appeared in the Melbourne Super 8 Group Newsletter Issue 135 in May 1998, 25 years after I solarized my first 25 feet of 16mm film of the Carlton Cemetery fence, just down the road from Goodtime Studios and did my first bit of sepia toning in a Russian processing tank that still lies with its warped plastic spiral in my garage in suburban Melbourne. As Pearls Before Swine sang in one of their songs, a faint memory now; 'The More things change, the more they stay the same'. They were not the first to say this. Technology continues to develop massively and the rubble of its passing slowly recedes to invisibility. I continue to live through this conundrum every day. It sings me to sleep. It wakes me up.