Turning Ocean Waters Acidic: Threatening Marine Life

21-24The most effective way to reduce atmospheric CO2 and ocean acidification would be to replace dirty fossil fuels with cleaner sources of energy

World squid fisheries

Peer reviewedPublisher PD

Free and Open Source Software for Everyone

14-19Want free, super useful software? Yes! We all do! If you think the best software is all products you have to pay lots of money for, then you haven’t looked hard enough

Plastics in the Oceans– Throttling Marine Life

23-29Plastic in marine ecosystems is an environmental issue that poses a serious threat to entire population of many marine species

Male copulatory behavior interrupts Japanese flying squid Todarodes pacificus female spawning activity

Batch spawning, intermittent spawning and multiple spawning represent common reproductive strategies among cephalopods. These flexible spawning strategies are also common in fishes, and are thought to be a female trait that is programmed depending on environmental parameters. The ommastrephid squid Todarodes pacificus, being a terminal spawner, is considered to have a single spawning event, extruding one large egg mass and dying soon thereafter. Females that are interrupted by males exhibiting mating behavior, while extruding the egg mass, spawn multiple egg masses over the course of 2-3 d instead of dying soon after spawning the first egg mass. We demonstrate that male mating behavior causes 'forced' intermittent spawning by females (i.e. more than one spawning event). We hypothesize that in T. pacificus, some males use this strategy to mate with females unable to repel advances while spawning, thus providing the male with the opportunity to contribute sperm and enhance gene flow

Spawning pattern of the neon flying squid Ommastrephes bartramii (Cephalopoda: Oegopsida) around the Hawaiian Islands

The neon flying squid, Ommastrephes bartramii, is an oceanic squid species that is widely distributed in the North Pacific, with the winter-spring cohort spawning around the Hawaiian Islands. Here, we investigated the spawning characteristics of O. bartramii by analyzing various reproductive parameters of individuals (622 males, 108 females) collected in this region. Female spawning status was determined from the somatic indices and histological characteristics of the ovaries. At all developmental stages, the ovaries of spawned females contained oocytes, and oviduct fullness was not correlated with body size. Thus, because the eggs mature asynchronously, with multiple filling and evacuation events, this species is considered an intermittent spawner. Mature males with developed accessory glands were also present within the distribution range of healthy spawned females, indicating that mating occurs between spawning events. Our data indicate that the first spawning event occurs at a mantle length of similar to 520-540 mm for Hawaiian O. bartramii. Subsequently, the squid forage and grow, and refill the oviducts, before the second spawning event occurs