The Effects of Heat Stress on the Physiology and Mortality of the Rhizostome Upside-Down Jellyfish <i>Cassiopea xamachana</i>—Observations Throughout the Life Cycle
This study was designed to investigate the impact of heat stress on the physiological changes and mortality rates of different life stages of the rhizostome jellyfish species <i>Cassiopea xamachana</i>, including planula larvae, scyphistomae (polyps), and medusae. Both larval and scyphis...
Saved in:
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-01-01
|
| Series: | Oceans |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2673-1924/6/1/6 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850280471834918912 |
|---|---|
| author | William K. Fitt Dietrich K. Hofmann Aki H. Ohdera Dustin W. Kemp André C. Morandini |
| author_facet | William K. Fitt Dietrich K. Hofmann Aki H. Ohdera Dustin W. Kemp André C. Morandini |
| author_sort | William K. Fitt |
| collection | DOAJ |
| description | This study was designed to investigate the impact of heat stress on the physiological changes and mortality rates of different life stages of the rhizostome jellyfish species <i>Cassiopea xamachana</i>, including planula larvae, scyphistomae (polyps), and medusae. Both larval and scyphistoma stages of <i>C. xamachana</i> are relatively tolerant to high temperatures, but both experience nearly 100% mortality at 36 °C. Increasing temperatures also induced stage-specific effects. Settlement rates of artificially induced larvae were near 100% at lower temperatures but decreased at 34–36 °C; larvae were dead at 36 °C. When scyphistomae of <i>C. xamachana</i> were subjected to a gradual increase in temperature from 28 to 38 °C, polyp size declined steadily in starved animals, with animals showing clear signs of temperature stress between 35 and 36 °C. Small medusae of <i>C. xamachana</i> pulsed more than larger medusae and tended to have peak pulse rates at higher temperatures (~35 °C) compared to larger medusae (~29–33 °C), though the latter was not significant. At a temperature of 39 °C, all the medusae exhibited signs of heat stress, including pulsing erratically (generally lower) rather than steady rhythmic pulsations, releasing copious amounts of mucus, and having withdrawn oral arms. Temperature data presented here, and in the literature, show that pulsing <i>C. xamachana</i> medusae exhibit a bell-shaped curve, with temperatures over 38 °C being detrimental and becoming lethal at 40 °C. Based on the findings of this study, it is proposed that the medusa stage of <i>C. xamachana</i> has a higher tolerance for elevated temperatures compared to both the larvae and the polyps. Predictions of global climate change indicate that populations of <i>C. xamachana</i> will likely face longer and hotter summer periods, leading to increased population sizes. However, higher temperatures pose a greater risk to the survival of the species as they increase mortality in the polyp and larval stages compared to the medusa stage. |
| format | Article |
| id | doaj-art-0215fa9fc74e47f39d9784aaebab2579 |
| institution | OA Journals |
| issn | 2673-1924 |
| language | English |
| publishDate | 2025-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Oceans |
| spelling | doaj-art-0215fa9fc74e47f39d9784aaebab25792025-08-20T01:48:45ZengMDPI AGOceans2673-19242025-01-0161610.3390/oceans6010006The Effects of Heat Stress on the Physiology and Mortality of the Rhizostome Upside-Down Jellyfish <i>Cassiopea xamachana</i>—Observations Throughout the Life CycleWilliam K. Fitt0Dietrich K. Hofmann1Aki H. Ohdera2Dustin W. Kemp3André C. Morandini4Odum School of Ecology, University of Georgia, Athens, GA 30602, USADepartment of Zoology and Neurobiology, Ruhr-University Bochum, 44801 Bochum, GermanyDepartment of Mathematics, University of Arizona, Tucson, AZ 85721, USADepartment of Biology, University of Alabama at Birmingham, Birmingham, AL 36294, USADepartamento de Zoologia, Instituto de Biociências, Universidade de São Paulo, São Paulo 05508-090, BrazilThis study was designed to investigate the impact of heat stress on the physiological changes and mortality rates of different life stages of the rhizostome jellyfish species <i>Cassiopea xamachana</i>, including planula larvae, scyphistomae (polyps), and medusae. Both larval and scyphistoma stages of <i>C. xamachana</i> are relatively tolerant to high temperatures, but both experience nearly 100% mortality at 36 °C. Increasing temperatures also induced stage-specific effects. Settlement rates of artificially induced larvae were near 100% at lower temperatures but decreased at 34–36 °C; larvae were dead at 36 °C. When scyphistomae of <i>C. xamachana</i> were subjected to a gradual increase in temperature from 28 to 38 °C, polyp size declined steadily in starved animals, with animals showing clear signs of temperature stress between 35 and 36 °C. Small medusae of <i>C. xamachana</i> pulsed more than larger medusae and tended to have peak pulse rates at higher temperatures (~35 °C) compared to larger medusae (~29–33 °C), though the latter was not significant. At a temperature of 39 °C, all the medusae exhibited signs of heat stress, including pulsing erratically (generally lower) rather than steady rhythmic pulsations, releasing copious amounts of mucus, and having withdrawn oral arms. Temperature data presented here, and in the literature, show that pulsing <i>C. xamachana</i> medusae exhibit a bell-shaped curve, with temperatures over 38 °C being detrimental and becoming lethal at 40 °C. Based on the findings of this study, it is proposed that the medusa stage of <i>C. xamachana</i> has a higher tolerance for elevated temperatures compared to both the larvae and the polyps. Predictions of global climate change indicate that populations of <i>C. xamachana</i> will likely face longer and hotter summer periods, leading to increased population sizes. However, higher temperatures pose a greater risk to the survival of the species as they increase mortality in the polyp and larval stages compared to the medusa stage.https://www.mdpi.com/2673-1924/6/1/6<i>Cassiopea</i>jellyfishrhizostome scyphozoanplanula larvascyphistomae polypmedusa |
| spellingShingle | William K. Fitt Dietrich K. Hofmann Aki H. Ohdera Dustin W. Kemp André C. Morandini The Effects of Heat Stress on the Physiology and Mortality of the Rhizostome Upside-Down Jellyfish <i>Cassiopea xamachana</i>—Observations Throughout the Life Cycle Oceans <i>Cassiopea</i> jellyfish rhizostome scyphozoan planula larva scyphistomae polyp medusa |
| title | The Effects of Heat Stress on the Physiology and Mortality of the Rhizostome Upside-Down Jellyfish <i>Cassiopea xamachana</i>—Observations Throughout the Life Cycle |
| title_full | The Effects of Heat Stress on the Physiology and Mortality of the Rhizostome Upside-Down Jellyfish <i>Cassiopea xamachana</i>—Observations Throughout the Life Cycle |
| title_fullStr | The Effects of Heat Stress on the Physiology and Mortality of the Rhizostome Upside-Down Jellyfish <i>Cassiopea xamachana</i>—Observations Throughout the Life Cycle |
| title_full_unstemmed | The Effects of Heat Stress on the Physiology and Mortality of the Rhizostome Upside-Down Jellyfish <i>Cassiopea xamachana</i>—Observations Throughout the Life Cycle |
| title_short | The Effects of Heat Stress on the Physiology and Mortality of the Rhizostome Upside-Down Jellyfish <i>Cassiopea xamachana</i>—Observations Throughout the Life Cycle |
| title_sort | effects of heat stress on the physiology and mortality of the rhizostome upside down jellyfish i cassiopea xamachana i observations throughout the life cycle |
| topic | <i>Cassiopea</i> jellyfish rhizostome scyphozoan planula larva scyphistomae polyp medusa |
| url | https://www.mdpi.com/2673-1924/6/1/6 |
| work_keys_str_mv | AT williamkfitt theeffectsofheatstressonthephysiologyandmortalityoftherhizostomeupsidedownjellyfishicassiopeaxamachanaiobservationsthroughoutthelifecycle AT dietrichkhofmann theeffectsofheatstressonthephysiologyandmortalityoftherhizostomeupsidedownjellyfishicassiopeaxamachanaiobservationsthroughoutthelifecycle AT akihohdera theeffectsofheatstressonthephysiologyandmortalityoftherhizostomeupsidedownjellyfishicassiopeaxamachanaiobservationsthroughoutthelifecycle AT dustinwkemp theeffectsofheatstressonthephysiologyandmortalityoftherhizostomeupsidedownjellyfishicassiopeaxamachanaiobservationsthroughoutthelifecycle AT andrecmorandini theeffectsofheatstressonthephysiologyandmortalityoftherhizostomeupsidedownjellyfishicassiopeaxamachanaiobservationsthroughoutthelifecycle AT williamkfitt effectsofheatstressonthephysiologyandmortalityoftherhizostomeupsidedownjellyfishicassiopeaxamachanaiobservationsthroughoutthelifecycle AT dietrichkhofmann effectsofheatstressonthephysiologyandmortalityoftherhizostomeupsidedownjellyfishicassiopeaxamachanaiobservationsthroughoutthelifecycle AT akihohdera effectsofheatstressonthephysiologyandmortalityoftherhizostomeupsidedownjellyfishicassiopeaxamachanaiobservationsthroughoutthelifecycle AT dustinwkemp effectsofheatstressonthephysiologyandmortalityoftherhizostomeupsidedownjellyfishicassiopeaxamachanaiobservationsthroughoutthelifecycle AT andrecmorandini effectsofheatstressonthephysiologyandmortalityoftherhizostomeupsidedownjellyfishicassiopeaxamachanaiobservationsthroughoutthelifecycle |