Unlike mammals, fishes reproduce by releasing eggs into the waters where they live and let them hatch outside their parents’ bodies. Thus, it is a great predicament for fish reproduction since they have to deal with external factors such as water current and predator population even before the eggs and larvae are actually born. Nonetheless, some species of fishes face greater difficulty due to their planktonic stages. The planktonic stage of some species of fishes is the release of the eggs into an environment different from that of the area where the adult fishes live and thrive (Bailey 45).
The parent fishes travels to a different part of the body of water such as the ocean and spawn. After which, they return to the area where they reside leaving the offspring far from them. The eggs and larvae are then, left on their own as they drift out during this stage of their existence. At this stage, many factors are involved on the probability of their survival. Some of these factors are water current, temperature, predator population, food abundance and even climate and seasonal changes.
Additionally, upon hatching, these schools of fishes deal with another problem, which is their transport to another place where their parents or ancestors originally came from. Connectively, Bailey and his associates investigated four different species of fishes having planktonic stages located in the Gulf of Alaska. They studied the different transport pathways of Pacific halibut, arrowtooth flounder, rex sole and Dover sole species of fish (Bailey 46). The study mainly focused on how these species migrate from the spawning site to nurseries located at different regions in the Gulf of Alaska.
Furthermore, the authors compared the effect of the different factors of transport mechanisms between the species under consideration. In the said study, the objectives are very specific and concise in spite of massive experiments and literature search the authors completed. The methodology was simple yet suitable for the experiments and the time frame is sufficient for the arrived conclusions. Since the time frame is extensive, about 30 years, even the water current alterations generated by seasonal changes were observed. The Gulf of Alaska setting was also discussed in detail.
The shelf features of the ocean were interestingly diverse thus; much data were obtained with high assurance of quality. The water currents were also examined vigorously and the descriptions were incredibly detailed. The setups, equipments and instruments are well-described such that one can say that everything was done accurately and with appropriate standards. For example, different types of nets were used for each set of fish with different stages of growth (Bailey 47). Moreover, each species of fish under research were described separately and were afterwards compared with each other regarding their distinctive transport mechanisms.
The study concluded that different species have different spawning periods throughout the year. Much of which can be derived from the characteristic reproduction processes each species possess. Patterns in egg and larval distributions were also different from species to species. Nevertheless, spawning transpires near the bottom and they only fluctuate in the vertical distribution of species, which can be accounted by their weight differences (Bailey 49). Upon comparison with the different species, the authors also evaluated their results by comparing them with the past historical data from literature.
Investigation of the effect of the different regions of the Gulf of Alaska also showed that egg and larval distributions are slightly affected and effects vary with species. In addition, juvenile fishes also differ with the type of species they belong such that soles are found in deeper waters than the halibut and arrowtooth flounder (Bailey 55). Looking into the movement of the young fishes, transport occurs in a multi-step, intricate process by means of various mechanisms and strategies, both biological and physical in nature.
The location of the spawns and nurseries are also crucial in the transport system of the species. Thus, circulation patterns, hydrography and temperature gradients influence the varying mechanisms of ocean transport. Interestingly, the rex sole, unlike its counterparts, have a wide range of spawning and nursery locations (Bailey 59). Upon adulthood, the fishes then track home via determination of the plethora of suitable food for each species. Amazingly, the food diet of the four species of fish under scrutiny is essentially similar.
The similarities of the food diet of the four species of fishes, unfortunately, are not included in the scope of the current research. Nevertheless, it is hypothesized that this result may be due to the fact that all the species dwell in the waters of the Gulf of Alaska (Bailey 63). To encapsulate the research, Bailey and his associates investigated the transport mechanisms utilized by four species of fishes, namely, arrowtooth flounder, Pacific halibut and Dover and rex soles, by surveying the different growth stages of the fishes and the regions where they are located.
They compared the effects of different factors manipulating the transport pathways of each species and also, related the results with the existing literature. Their study resulted in a number of observations on how these species migrate in the Gulf of Alaska prior, during and after reproduction. On the other hand, further studies are still recommended regarding other factors that affect transport mechanisms, which are not part of the study such as human intrusion, i. e. fishing (Bailey 64).
It is further recommended that studies on whether the parent species revisit and spawn on the same site every mating season should be initiated. The study is quite fascinating since it is a very significant way to monitor and even control if need be, the breeding rate of these fishes. By learning these things, one can monitor their population and thus, protect them from extinction in the near future. Researches such as these should be done to supervise our marine resources, this time, with other species of fishes.