Effects of Varying Salinities on Clinging Jellyfish (Gonionemus Vertens) Polyps

Overview

Clinging jellyfish, or Gonionemus vertens, are small, invasive hydrozoan jellyfish that pose a threat to the public, as well as our ecosystems. This species is native to the northern Pacific Ocean, but has recently been sighted in areas of the northern and western Atlantic Ocean, making its first appearance off the coast of New Jersey in the Manasquan and Shrewsbury Rivers in 2016. These jellyfish can overpopulate and crowd waterways and vegetation, overwhelming and killing fish species both in the wild and aquaculture settings, such as fish farms. In addition, G. vertens are also extremely dangerous to humans. A recent resurgence of these jellyfish has brought on a wave of more toxic stings, possibly a separate variant then the population of G. vertens first observed in other locations of the northern Pacific. These jellyfish produce extremely potent stings associated with severe physical and neurological symptoms and pain, and often result in hospitalization. G. vertens 'cling' to vegetation such as eelgrass, which grows in shallow waters off various estuaries and rivers, in the same areas that the public utilizes for recreational swimming, fishing, and water sports. These jellyfish therefore pose a danger to both public health and the local economy. The goal of this experiment was to pinpoint which environmental factors allow G. vertens to grow and thrive so we can better predict where these jellyfish may appear next, as well as mitigate the negative effects these organisms pose on the public. To do this, we placed G. vertens polyps in tanks with three different salinities, 15 ppt, 25 ppt, and 30 ppt, and evaluated them over a ten month period. We conducted a population assessment of these polyps once per month in order to quantify the change in polyp growth. Throughout the duration of this experiment, all forms of polyps degenerated in each of the three salinity treatments. Overall, however, we found 30 ppt to be the salinity that best supports G. vertens populations. Salinity levels of 30 ppt yielded the highest number of adult polyps, and the lowest number of tissue masses, or polyps in a state of dormancy. Moving forward, we can use this data to better understand the preferences of G. vertens, as well as better predict potential migration patterns.

Competition history

• AJAS 2025 Category not listed

Related projects

Closest projects by meaning, across every fair and year in the corpus.

Browse more like this

• AJAS None projects
• Every AJAS 2025 project