24. Parental care in fishes.........pptx

Parental care can be defined as an association between the offspring and parents as to increase the chances of survival of offsprings. Parental care is not commonly seen in fishes, only the class cichlidae shows the parental care by brooding their offsprings.

1. DEPARTMENT OF ZOOLOGY PRESENTED BY: TAIMOOR WASEEM REG NO: 20M-UOC/ZOL-24 BS-ZOOLOGY SESSION 2020-2024 COURSE TITLE: ICHTHYOLOGY SUBMITTED TO: DR. SYEDA NADIA AHMAD TOPIC: PARENTAL CARE IN FISHES

2. Parental care in fishes Taimoor waseem

3. INTRODUCTION Parental care can be defined as an association between the parents and the off springs, so as to increase the chances of the survival of the young ones, and in fishes it includes all the post-spawning care of the off springs by the parents. Most fishes do not care for their eggs or youngs and leave the spawning grounds soon after fertilization. The lack of parental behaviour is correlated with production of great numbers of eggs and sperms. But there are many fishes where definite parental care has been evolved. (Parental Care - an Overview | ScienceDirect Topics, n.d.)

4. Patterns of Parental behavior in fishes Maternal Care : Maternal care in fishes involves the mother providing care and protection to her offspring. This can include activities such as nest building, egg guarding, fanning, and defending the eggs or young fish from predators. Maternal care is widespread among various fish species, particularly those that lay eggs. For instance, in some species of cichlids and Siamese fighting fish (Betta splendens). ( Balshine , 2012)

5. Patterns of Parental behavior in fishes Paternal Care: Paternal care involves the father taking on the responsibility of caring for the offspring. While less common than maternal care, paternal care is observed in various fish species. This can include activities such as egg guarding, nest building, and even mouthbrooding, For example, in seahorses, pipefish, and some species of cichlids.( Balshine , 2012)

6. Patterns of Parental behavior in fishes Biparental Care: Biparental care occurs when both parents contribute to the care and upbringing of the offspring. Biparental care is observed in various fish species, and it often provides benefits such as increased offspring survival and growth rates. For example, in certain species of angelfish, both parents participate in cleaning and guarding the nesting site, as well as fanning the eggs to ensure proper oxygenation and development. ( Balshine , 2012)

7. Methods of parental care in fishes Following are the different types or methods of parental care in fishes: Depositing Eggs in Suitable Places. Nest Building. Mouth Cavity as Shelter. Coiling Round Eggs. Attachment to Body. Formation of Integumentary Cups. Development of Brood Pouches. Mermaid’s Purses. Viviparity .(Meghana,2016)

8. Methods of parental care in fishes Depositing Eggs in Suitable Places : A number of fish species have developed some design of depositing their eggs in suit­ably protected places. (a) Deposition of eggs in sticky cove­ring: ( i ) In carps, eggs are usually laid with some special sticky covering by means of which they are attached to each other or to stones, weeds etc. (Meghana,2016)

9. Methods of parental care in fishes (ii) In yellow perch ( Perca flavescens ) eggs are deposited in a rope-like structure The eggs are held together by a long floating membrane. (iii) Angler fish (Lophius) lay their eggs invested by a gelatinous external coat, that remain together to form a transparent mass of enormous size. (Meghana,2016) Fig#1: (A).Eggs deposited in a Roop like structure in yellow perch.(B).Eggs deposited in a gelatinous outer coat in Angler fish.(C).Eggs deposited on a sticky thread secreted from the kidney of flying fish.(https://images.app.goo.gl/G5sMFPh1Fxyodu4o7)

10. Methods of parental care in fishes (b ) Eggs scattered over aquatic plants: Eggs of fishes such as pikes (Esox lucius ), carps (Cyprinus carpio ), Carrassius auratus etc., are scattered over aquatic plants to which they remain attached. (c ) Eggs deposited on dead shells of bivalves: Females of European bitterling ( Rhodeus amarus ) deposit eggs in the siphon of a fresh-water mussel by means of a long tube acting as an ovipositor .(Meghana,2016)

11. Methods of parental care in fishes This ovipositor is a long tube drawn out from the oviduct. After oviposition male Rhodeus immediately sheds the sperm over the eggs and then guards them. The male Rhodeus , interestingly, are not sexually excited by the presence of the female of its own species, but by the sight of the shell of the mussel in which the eggs have been deposited. .(Meghana,2016) Fig # 2.Oviposition by European butterling on the shells of a dead mussel (https://images.app.goo.gl/Tezrk8SUY47gFWWD6)

12. Methods of parental care in fishes B.Nest Building: Some fishes prepare crude nests for egg laying. At first a suitable place for preparing the nest is selected and some species may defend the place till death. Males of many species like the Darters ( Etheostoma ), sunfishes and cichlids, prepare a shallow basinlike nest for laying eggs by females. The stones and pebbles are removed from such nest and male keeps close watch over the eggs till hatching. (Meghana,2016)

13. Methods of parental care in fishes Types of nest building a)Unprotected nest: A few species, however, leave the nest unprotected. Many freshwater fishes prepare crude nest with aquatic vegetation where eggs are laid. Protopterus and Lepidosiren prepare deep hole into which the females lay eggs. Males protect the nest till development is complete. (Meghana,2016)

14. Methods of parental care in fishes b)Crude nest: The fertilized ova are protected by male who keeps guard over the nest till the young ones are hatched. The young ones are allowed to leave the nest in a body under the protection of father. Both the male and female of some cat fishes of North America prepare a crude nest in the mud for egg-laying. The nest is sometimes provided with protective cover of logs, stones, etc. (Meghana,2016)

15. Methods of parental care in fishes c)Nest in dead aquatic weeds: Most interesting example is provided by the male stickleback Gasterosteus aculeatus, a small freshwater fish of North American lakes and ponds. The male fish actually builds a nest of dead aquatic weeds which are joined together by a sticky secretion produced from the kidneys. When the nest assumes a considerable size, the male makes a small tunnel. After the formation of tunnel and an elaborate courtship ritual, the male drags a mature female into the tunnel for laying eggs. After laying eggs, the female swims away and the male keeps watch over the fertilised eggs till development is over.(Meghana,2016) Fig #3.Male stickleback forming nest.(https://images.app.goo.gl/po3zosDgYRUENoFk8)

16. Methods of parental care in fishes d)Foamy nest: Foamy nest prepared by blowing of bubbles of air and sticky mucus are also encountered in many fishes. The bubbles of air and mucus adhere to form a floating mass of foam. The eggs are collected by the male in his mouth cavity and he throws them in such a way that the eggs can adhere to the lower surface of foamy nest. This type of caring for eggs is found in Betta, Macropodus and many other fishes.(Meghana,2016) Fig #4.Paradise fish ( Macropodus opercularis ) forming foamy nest.(https://images.app.goo.gl/54LzDat1kieHBKbY6).

17. Methods of parental care in fishes C. Mouth Cavity as Shelter: In some species, eggs develop within the mouth of the parent. In many cichlids, the female carries the eggs in her oral cavity. After hatching, the young fry does not leave the shelter for some time, and swim about in water very near the mouth, so that they can return to it in case of danger (found in Tilapia). In the cat fish, Arius the male carries the eggs and young ones in his mouth, and does not take food during this period.(Meghana,2016) Fig#5.Mouth cavity as shelter.(https://images.app.goo.gl/kxxRfTj7RvkKdwJB9)

18. Methods of parental care in fishes D. Coiling Round Eggs: In butter fish, Pholis rolls the eggs into a rounded ball and then one of the parents remains on guard, possibly male, guards the egg-ball by coiling round it. (Meghana,2016) Fig#6.Butterfish coiliing round the eggs.(https://images.app.goo.gl/Az3LET18K41yhP8r8)

19. Methods of parental care in fishes E. Attachment to Body: In Kurtus indicus (Perciformes) the male develops a bony hook projecting from the forehead and is supported by a special process of skull bone. The eggs are grouped in two bunches with the help of filamentous processes of the egg membrane. The eggs are attached to the hook of the forehead, in such a way that one bunch of eggs lies on either side of the head of the male, as he swims in water. (Meghana,2016) Fig # 7.Kurtus indicus carrying in situ egg mass.(https://images.app.goo.gl/DDHprZNyHVzyUf176)

20. Methods of parental care in fishes F. Formation of Integumentary Cups: In a cat fish, Platystacus of Brazil, shows an interesting method of parental case. During breeding season, the skin of lower surface of the body of the female fish becomes soft and spongy. Immediately after fertilisation of the eggs, the female presses her body against the eggs in such a way that each egg becomes lodged in a small integumentary depression. Each egg is attached inside the cup by an inconspicuous stalk. The eggs remain in this position till hatching. (Meghana,2016) Fig#8.Plystacus bear eggs in integumentary cups.(https://images.app.goo.gl/H73X2fmq6RhiEsso6)

21. Methods of parental care in fishes G. Development of Brood Pouches : In the pipe fish, Syngnathus and the sea horse, Hippocampus the eggs develop within the broad pouch of the male. The eggs are transferred into the brood pouch by the female and development takes place within the brood pouch. (Meghana,2016) Fig#9: Development of brood pouch.(https://images.app.goo.gl/mbK7AaC7Ngvdh7Yj7)

22. Methods of parental care in fishes H. Mermaid’s Purses: Oviparous sharks (e.g., Scyllium ) lay fertilized eggs inside the protective horny egg capsules or mermaid’s purses, which remain anchored to the sea weeds by their long tendrils. The young hatch out after rupturing the egg case . (Meghana,2016) Fig#10.Mermaid's purses(https://images.app.goo.gl/d9qX6p99nLXRLwWg6)

23. Methods of parental care in fishes I. Viviparity : The highest degree of parental care is found in viviparous fishes where young develop within the oviduct of the female. A few species are viviparous, such as the dog-fish, Scoliodon and the surf fish Cymatogaster aggregatus . Both fertilization and development are internal. Developing embryos are nourished mostly by a yolk sac placenta and the young are born with the characteristic of the adult. Viviparity provides maximum protection and represents the highest degree of parental case.(Meghana,2016) Fig#11.Body cavity of cymatogaster aggregate.(https://images.app.goo.gl/XYcXPJ7fTXANupsN7)

24. Cost and benefits of parental care Benefits of Parental Care: Survival. Protection. Contribute to reproductive fitness. Increased growth rate and quality. Better development. (Goldberg et al., 2020)

25. Cost and benefits of parental care Costs of Parental Care: Reduced foraging : Time and energy spent guarding eggs or fry limit the parent's ability to find food for themselves. This can negatively impact their health and future reproductive success . Increased vulnerability : Caring parents become more conspicuous and potentially more susceptible to predation themselves. (Goldberg et al., 2020)

26. Human impact on parental care in fishes Human activities can significantly affect parental care in fish populations through various environmental changes and resource disruptions. Here's a closer look at some of these impacts: 1. Habitat Destruction and Degradation : Coastal development, dredging, and pollution can destroy spawning grounds and nursery habitats crucial for parental care. Disrupted habitats can make it difficult for fish to find suitable nesting sites or expose eggs and fry to higher predation risks. (McGhee & Bell, 2014)

27. Human impact on parental care in fishes 2. Overfishing: Overfishing can deplete fish populations, impacting the breeding stock and potentially disrupting mating systems. This can lead to a decline in the number of breeding pairs and individuals available for parental care. 3. Pollution: Water pollutants can have various detrimental effects on parental care behavior. Pollutants can harm the health of both parents and offspring, reduce foraging efficiency, and alter parental instincts. (McGhee & Bell, 2014)

28. Human impact on parental care in fishes 4. Introduction of Invasive Species: Invasive fish species can compete with native fish for resources and spawning grounds. This competition can disrupt parental care behaviors and reduce the survival of offspring in native species . 5. Climate Change: Rising water temperatures and ocean acidification can disrupt fish physiology and reproductive cycles. This can lead to changes in parental care behavior, spawning times, and overall reproductive success. (McGhee & Bell, 2014)

29. Parental care across different fish taxa: Fish Taxa Parental Care Seahorses and Pipefishes (Family Syngnathidae) Male pregnancy: males carry fertilized eggs and developing embryos in a brood pouch, providing nourishment and protection until birth(Wilson, 2001) Mouthbrooding African Cichlids (Genus Tilapia) Mouthbrooding: parents carry fertilized eggs or fry in their mouths until they hatch(Duponchelle et al., 2008) Anabantoids (Family Osphronemidae) Bubble nest building: males construct nests and guard eggs until they hatch, sometimes assisting in fry care (Kidd et al., 2012)

30. Parental care across different fish taxa: Catfishes (Order Siluriformes) Nest building and protection: some species build shelters for spawning and guard eggs and fry (Kidd et al., 2012) Cichlids (Family Cichlidae) Diverse care: nest building, brood protection, and mouthbrooding by one or both parents (Kidd et al., 2012) Sticklebacks (Family Gasterosteidae ) Moderate care: nest building, brood protection, and territoriality by one or both parents (Kidd et al., 2012)

31. Parental care across different fish taxa: Killifishes (Family Cyprinodontidae) Variable care: some guard nests or eggs, but generally less parental involvement (Kidd et al., 2012) Salmonids (Family Salmonidae) Limited care: nest building and minimal egg protection (Kidd et al., 2012) Sharks (Order Selachii) Internal gestation: embryos develop inside the mother but no parental care after birth (Kidd et al., 2012) Lampreys (Order Petromyzontiformes) No care: semelparous breeding, adults die after spawning and leave eggs unattended. (Kidd et al., 2012)

32. Conclusion In conclusion, parental care in fishes demonstrates a remarkable diversity of strategies evolved to ensure offspring survival. From nest building to mouthbrooding, these behaviors reflect a delicate balance between investing in offspring and the parent's own reproductive success and survival. While providing clear benefits to offspring, such as protection from predators and optimal environmental conditions, parental care also incurs costs for parents, including increased energy expenditure and predation risk.

33. references McGhee, K. E., & Bell, A. M. (2014). Paternal care in a fish: epigenetics and fitness enhancing effects on offspring anxiety. Proceedings of the Royal Society B: Biological Sciences, 281(1794), 20141146. https://doi.org/10.1098/rspb.2014.1146 . Goldberg, R. L., Downing, P. A., Griffin, A. S., & Green, J. P. (2020). The costs and benefits of paternal care in fish: a meta-analysis. Proceedings of the Royal Society B: Biological Sciences, 287(1935), 20201759. https://doi.org/10.1098/rspb.2020.1759 . Parental Care - an overview | ScienceDirect Topics. (n.d.). Www.sciencedirect.com. https://www.sciencedirect.com/topics/neuroscience/parental-care Meghana, G (2016, October 20). Parental Care in Fishes | Zoology. Zoology Notes. https://www.notesonzoology.com/fish/parental-care-in-fishes-zoology/4464

34. references Balshine , S. (2012). Patterns of parental care in vertebrates. The Evolution of Parental Care, 62–80. https://doi.org/10.1093/acprof:oso/9780199692576.003.0004 Kidd, M. R., Duftner , N., Koblmüller , S., Sturmbauer , C., & Hofmann, H. A. (2012). Repeated Parallel Evolution of Parental Care Strategies within Xenotilapia , a Genus of Cichlid Fishes from Lake Tanganyika. PLoS ONE, 7(2), e31236. https://doi.org/10.1371/journal.pone.0031236 Wilson, A. B. (2001). Male Pregnancy in Seahorses and Pipefishes (Family Syngnathidae): Rapid Diversification of Paternal Brood Pouch Morphology Inferred From a Molecular Phylogeny. Journal of Heredity, 92(2), 159–166. https://doi.org/10.1093/jhered/92.2.159 Duponchelle , F., Paradis, E., Ribbink , A. J., & Turner, G. F. (2008). Parallel life history evolution in mouthbrooding cichlids from the African Great Lakes. Proceedings of the National Academy of Sciences, 105(40), 15475–15480. https://doi.org/10.1073/pnas.0802343105