Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Aquarium Fishes Are More Aggressive in Reduced Environments

23.09.2011
An angry glare from the family goldfish might not be the result of a missed meal, but a too-humble abode. Fish in a cramped, barren space turn mean, a study from Case Western Reserve University has found. Ornamental fishes across the U.S. might be at risk, all 182.9 million of them.

“The welfare of aquarium fishes may not seem important, but with that many of them in captivity, they become a big deal,” said Ronald Oldfield, an instructor of biology at Case Western Reserve. Why, then, has the welfare of pet fishes been overlooked among the scientific community?

Oldfield is the first to scientifically study how the environment of home aquariums affects the aggressive behavior of ornamental fishes. The results are published in the online edition of Journal of Applied Animal Welfare Science, volume 14, issue 4.

Oldfield compared the behavior of Midas cichlids (Amphilophus citrinellus) in a variety of environments: within their native range in a crater lake in Nicaragua, in a large artificial stream in a zoo, and in small tanks of the sizes typically used to by pet owners.

The study focused on juvenile fish to remove aggressive behavior related to mating. Also, resources such as food and shelter were removed prior to observation to eliminate direct competition.

Along with environment size, Oldfield tested the complexity of an environment and the effects of number of fish within tanks.

The addition of obstacles and hiding places using rocks, plants, or other similar objects can increase the complexity of the aquarium environment.

He found that an increase in tank size and complexity can reduce harmful aggressive behaviors, and make for healthier fish at home.

Oldfield quantified aggressive behavior as a series of displays and attacks separated by at least a second. Displays are body signals such as flaring fins. An attack could be a nip, chase, or charge at another fish.

In aquariums, these behaviors can lead to injury and in extreme cases to death.

Aggressive behavior was not correlated with small-scale changes in either group size or habitat size alone. However, a significant difference was observed in environments sufficiently large and complex: fish spent less time exhibiting aggressive behavior.

This more natural environment elicits more natural behaviors, which are more interesting to observers, Oldfield said.

And, for the fish themselves, their lives can be vastly improved with these simple changes to their environments.

“If we are going to try to create a society as just as possible, we need to do everything we can to minimize negative effects,” Oldfield said.

But why should anyone beyond fish enthusiasts care about fish behavior?

Minimizing negative effects extends beyond the treatment of ornamental fishes. Interactions between humans and other species could apply.

Humans have intimate relationships with a variety of fishes. They provide food and sport for many people. Some are used for decoration, and others are well-loved pets or may become addicting hobbies.

Additionally, conditions for animals in the rapidly growing field of aquaculture and on factory farms are issues of contention.

Oldfield is not trying to support any extreme agendas. “I’m not trying to ban human use of animals– I just think that if we are going to interact with them then we should be as informed as possible.”

Relatively simple fish behavior can also serve as a basic model for more complex behaviors.

In the future, Oldfield said “This study might help us to better understand how human behavior changes when people are placed in different social environments.” Violence in prisons might be linked in part to the smaller space and reduced stimuli.

Until then, the 182.9 million ornamental fishes in the United States may benefit from this study. The family goldfish can swim in peace, enjoying the remodeled space.

Release prepared by Jeremy Rayl, Case Western Reserve University student.

Kevin Mayhood | Newswise Science News
Further information:
http://www.case.edu

Further reports about: Aquarium aggressive aggressive behavior environments negative effects

More articles from Studies and Analyses:

nachricht Antarctic Ice Sheet mass loss has increased
14.06.2018 | Technische Universität Dresden

nachricht WAKE-UP provides new treatment option for stroke patients | International study led by UKE
17.05.2018 | Universitätsklinikum Hamburg-Eppendorf

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

Im Focus: Photoexcited graphene puzzle solved

A boost for graphene-based light detectors

Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Carbon nanotube optics provide optical-based quantum cryptography and quantum computing

19.06.2018 | Physics and Astronomy

How to track and trace a protein: Nanosensors monitor intracellular deliveries

19.06.2018 | Life Sciences

New material for splitting water

19.06.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>