Water striders are fascinating insects known for their ability to “walk on water” due to the surface tension of water and their hydrophobic legs. They can be found in various aquatic habitats, including ponds, lakes, swamps, and streams, where they feed on prey captured in fast-flowing regions of currents.
An interesting question arises when we consider whether water striders can also walk on oil. Oil has different properties than water, so it’s worth exploring if these insects can maintain their mobility on such surfaces. In the following article, we’ll delve into the science behind water striders’ incredible ability and examine how it might translate to walking on oil surfaces.
Water Striders: An Overview
Family Gerridae
Water striders belong to the family Gerridae. They are insects known for their unique ability to walk on water, made possible by their long legs and water-repellent hairs.
Habitats and Range
These fascinating creatures can be found in various freshwater habitats, such as:
- Ponds
- Lakes
- Creeks
Generally, water striders live in the Northern Hemisphere and are common around bodies of water inhabited by their primary prey.
Species and Diversity
There is substantial species diversity within the Gerridae family, including several species found in North America. Different water striders can vary in size, shape, and color, but all share the distinctive characteristic of walking on water.
Diet and Prey
Water striders have a varied diet, feeding on:
- Mosquito larvae
- Midge
- Tadpoles
- Other small aquatic insects
By skating on the water’s surface, they can quickly hunt and capture their prey.
The following table offers a brief comparison between different aspects of water striders’ lives:
| Aspect | Description |
|---|---|
| Habitats | Freshwater environments, such as ponds, lakes, and creeks |
| Range | Primarily found in the Northern Hemisphere |
| Diet | Mosquito larvae, midge, tadpoles, and other small aquatic insects |
| Unique Characteristics | Ability to “walk on water” due to long legs and water-repellent hairs |
Unique Features and Adaptations
Hydrophobic Legs and Microscopic Hairs
Water striders possess unique features that enable them to “walk” on water surfaces. One such adaptation is their hydrophobic legs. These water-repelling legs help them stay afloat by preventing contact between water molecules and their legs. Additionally, microscopic hairs on their bodies and legs work to keep them dry and enhance buoyancy1. For instance, the velvety hairs on their bodies repel water while skating across the water surface2.
Surface Tension and Buoyancy
Another critical adaptation is the ability to utilize surface tension and buoyancy. Water striders take advantage of the high surface tension of water to support their weight3. By distributing their weight across the water surface, they create small indentations, or air bubbles, that help maintain buoyancy4.
Here’s a comparison table of some key features of water striders:
| Feature | Function |
|---|---|
| Hydrophobic Legs | Prevent contact with water molecules, helping them stay afloat |
| Microscopic Hairs | Enhance buoyancy and repel water |
| Surface Tension | Support their weight on the water surface |
| Buoyancy and Weight Distribution | Create small air bubbles to maintain buoyancy, aiding in locomotion |
These adaptations showcase how water striders excel in their aquatic environment. However, it’s essential to note that their skills may not directly transfer to walking on oil, as the properties of oil and water are different. Further research would be required to determine their performance on other liquids besides water.
Locomotion on Different Surfaces
Walking on Water
Water striders, also known as water bugs or water skeeters, have a unique ability to walk on water due to their hydrophobic legs and distributed weight. They achieve this through:
- High surface tension of water
- Long, hydrophobic legs
- Evenly distributed weight
Effects of Oil and Hydrophobic Surface
Though water striders typically reside on water surfaces, they might face challenges when encountering oil. The biomechanical factors involved in their locomotion can be affected by different surface properties, such as:
- Surface tension
- Fluidity of the liquid
- Degree of hydrophobicity
Table 1: Comparison of Locomotion Factors on Water and Oil
| Surface | Surface Tension | Fluidity | Hydrophobicity |
|---|---|---|---|
| Water | High | Variable | Low |
| Oil | Low | High | High |
Distributed Weight and Locomotion
Water striders use their distributed weight to maintain balance while moving. Key factors contributing to this ability are:
- Unique leg structure
- Sculling motion with middle legs
- Efficient momentum transfer
Examples of distributed weight adaptation in water striders:
- Staying afloat by evenly spreading their legs on the surface
- Using curved legs to maintain contact with the surface during motion
- Maximizing the use of surface tension for effective propulsion
These factors ensure water striders can efficiently move on water surfaces while adapting to different environmental conditions, though the interaction with oil surfaces remains an area of research.
Life Cycle and Reproduction
Eggs and Substrate
Water striders lay their eggs on various substrates found in their environment, such as rocks and plants 1. Examples of common substrates include:
- Aquatic plant leaves
- Small pebbles
- Twigs
Laying eggs on different substrates offers some advantages:
- Protection from predators
- Suitable environment for growth
- Different attachment points for the eggs
Life Stages
The water strider life cycle consists of three stages:
- Eggs: Hatching takes place within a few weeks, depending on temperature and other factors.
- Nymphs: Water striders go through several molts, shedding their exoskeleton while growing. They resemble the adult form but lack wings.
- Adults: Once fully developed, water striders gain functional wings and reach sexual maturity, ready for reproduction.
Hibernation
As winter approaches, water striders often enter a state called hibernation. This period allows them to survive in colder environments by:
- Reducing metabolism
- Conserving energy
Water striders usually seek shelter among plant debris, mud, or rocks during hibernation 2.
Interaction with Environment and Predators
Predation on Water Striders
Water striders, being aquatic insects, face various predators in their natural habitat. Some common predators include:
- Spiders: Certain species of spiders can prey on water striders.
- Birds: Many bird species feed on insects, including water striders.
These predators take advantage of the water striders’ unique habit of walking on the water’s surface. However, water striders have developed certain adaptations to help protect themselves.
Avoiding Predators
Genital shield: One adaptation water striders have is a structure called the genital shield, which offers protection from predators while mating.
Surface adaptation: Water striders utilize the high surface tension of water to stay above water and avoid certain predators.
Oil interaction: Water striders generally prefer to be on the water’s surface, but it is unclear how they would interact with oil spills. During an oil spill, the surface tension may be affected, and it could pose challenges for water striders. More research may be needed to understand the relationship between water striders and oil spills.
Comparison table:
| Predator | Water Strider Defense |
|---|---|
| Spiders | Genital shield |
| Birds | Surface adaptation |
To sum up, water striders interact with their environment and predators primarily by taking advantage of the surface tension of water, and they have developed certain adaptations to protect themselves. More research is needed to understand how these fascinating creatures interact with oil spills.
Evolution and Scientific Studies
Evolution of Water Striders
Water striders, also known as Jesus bugs, are part of the Hemiptera order, which consists of true bugs. They are known for their ability to walk on water, thanks to their unique evolutionary adaptations. These adaptations include:
- Hydrofuge hairs on their legs that repel water
- Air pockets formed by the hairs, for buoyancy
- Wings for quick escape from predators
Their habitat includes wet environments such as vernal pools, mud puddles, and other bodies of water1. As part of their evolutionary journey, water striders developed strategies to minimize the contact area with water, allowing them to stand and move on the surface, utilizing surface tension.
Materials and Technologies Inspired by Water Striders
The fascinating ability of water striders has sparked interest in developing materials and technologies that mimic their water-repelling properties. Some key inspirations derived from water striders include:
- Surfaces with hydrophobic coatings to repel water
- Robotics that can walk on water, designed to aid research and environmental studies2
A comparison of water striders with inspired technologies:
| Feature | Water Striders | Inspired Technologies |
|---|---|---|
| Water Repellency | Hydrofuge hairs on legs | Hydrophobic coatings on surfaces, materials |
| Buoyancy | Air pockets formed by hairs | Air-filled or lightweight components |
| Movement | Water surface tension, leg action | Robotics mimicking leg movements |
By learning from the evolutionary adaptations of water striders, researchers can design and develop materials and technologies with improved water-repelling capabilities.
Footnotes
Reader Emails
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.
Letter 1 – Water Strider
Subject: Texas Pool Bugs
Location: Texas
October 28, 2013 8:07 am
please tell me what this thing is!!! have no clue
Signature: thank you TRay
Dear TRay,
We wish we had more photos of Water Striders on our site. They are amazing true bugs that spend their immature phase skating across the water in search of prey, especially insects that fall onto the water’s surface. When they attain adulthood, they are capable of flight.
Letter 2 – Water Strider from China
Subject: Water Strider from China
Location: Shijiazhuang, Hebei, China
August 5, 2017 6:21 pm
Dear Bugman,
what’s a common water strider in China? To be specific, Hebei Province. Is it the genus Gerris?
Thank you and kind regards,
Signature: Peter
Dear Peter,
You are correct that this is a Water Strider in the family Gerridae, but we do not have the necessary skills to further classify it to the genus or species level. According to BugGuide: “fine water-repellant hairs on the underside of the tarsi allow the bug to walk on water’s surface.”
Letter 3 – Water Strider: Countdown only Two more postings until 20,000
Subject: water striders
Location: Riverbend Park, Fairfax, Virginia
April 3, 2015 7:09 am
I found these water striders in a quiet part of a small stream going into the Potomac River in Riverbend Park, Virginia. They are clasping each other, but isn’t it a bit early for mating? If you can identify the species that would be great, too. Thank you for your wonderful site.
Signature: Seth
Hi Seth,
Thanks for sending in your wonderful image of a Water Strider, an aquatic insect that is able to disperse its weight so that it can skate across the surface of the water without breaking the tension.
Hi Daniel –
It looks like somehow you only got one of the water strider images I sent; here is the photo that may have gotten lost, showing one strider clasping another:
Regards, Seth.
Hi again Seth,
Thanks so much for forwarding what appears to be a mating or courtship image of a pair of Water Striders.
Letter 4 – Water Strider from Thailand
Subject: Bug from natural pool near Chiang Mai, Thailand
Location: Near Chiang Mai, Thailand
March 7, 2015 10:14 pm
G’day Bugman,
My wife and I were enjoying our honeymoon throughout SE Asia, and in one spot near Chiang Mai I came across an insect the likes I have never encountered before
Signature: John
Dear John,
This is a Water Strider in the family Gerridae, a group of insects that are also known as “Pond Skaters, Jesus Bugs, Water Skippers” according to BugGuide, a North American insect website. Water Striders skim across ponds and other bodies of water on long legs that distribute the insect’s weight so as not to break the tension of the surface of the water. Water Striders prey on insects that fall into the water. Here is an image from the Insects of Thailand site. We suspect your individual is immature as it does not have fully developed wings, but we cannot say for certain as we believe some species of Water Striders are wingless.
Letter 5 – Water Striders
More Water Striders
November 24, 2009
Hi Bugman,
I saw your comment about the dearth of water striders on WTB, so I thought I’d send these your way. The first one I’m pretty sure is Aquarius remigis based on images on BugGuide and its large size. According to BugGuide this is one of the largest and most common water striders in North America. The second one looks like something different though, based on the white markings on the thorax and abdomen. My best guess is something in the genus Gerris but there’s only one image on BugGuide that looks close. Both of these were found in August 2008, running around on Cascade Creek, Minnesota in large groups.
Joel Gardner (clickbeetle)
Cascade Creek (near Grand Marais, MN)
Hi Joel,
Thanks so much for your wonderful contribution of additional Water Strider images for our website.
Letter 6 – Water Striders
Subject: Water Striders
Location: Tucquan Glen, Lancaster County PA
October 29, 2013 10:36 am
Hi Daniel!
I read your comment about wishing you had more photographs of water striders. I attached a few shots that I took several weeks ago at Tucquan Glen in Lancaster County PA.
There are two shots of an adult with prey and a group of young individuals. They were not easy to photograph due to their constant motion.
Melody McFarland
Lancaster PA
Signature: Melody McFarland
Hi Melody,
Thanks so much for supplying some additional photos of Water Striders in the family Gerridae for our site. We see from the metadata on the digital image that your photos were taken on September 26, 2013. It appears that the adults do not have wings, so we thought they might be nymphs as well, but your individuals resemble this photo from BugGuide of a member of the genus Trepobates which BugGuide indicates: “Superficially resembles nymphs of Gerris. First antennomere shorter than three others combined.” Water Striders are perfectly adapted for skating across the surface of the water, and according to BugGuide: “fine water-repellant hairs on the underside of the tarsi allow the bug to walk on water’s surface; only the mid- and the hind legs are used for locomotion; they are attached to large coxae connected to the sides of the thorax and are unfit for walking on land.”
Alas, we haven’t the necessary skills to distinguish one species from another or even to definitively determine the correct genus, so our identification might be incorrect. Your photos which illustrate the feeding habits are a marvelous addition to our archive.
Letter 7 – Water Striders eat Leaf Hopper
Subject: What are these little water bugs?
Location: Boulder Colorado
August 1, 2012 8:24 pm
Hey Bugman!
I saw these little creatures today here in sunny Colorado in a small pool of water. At first glance they looked like some sort of fly that would stride on the water. While watching them for awhile longer, a leaf hopper jumped into the water and suddenly every one of these water flies swarmed it and devoured the leaf hopper! What are they?!
Signature: Michael Lohr
Hi Michael,
These are Water Striders in the family Gerridae. They are able to skate across the surface of calm bodies of water without sinking thanks to a wide leg span that disperses the weight as well as water repellent hairs on their legs. According to BugGuide, they are found “surface of temporary or permanent ponds, and slow-moving areas of streams and rivers” and they feed on “small living or dead insects on the water surface.” We are not certain if these are immature Water Striders or if they are just a very small species.
Letter 8 – Water Striders from Ghana
November 20, 2009
The following water bug pix were taken at Hans Botel Cottage, Cape Coast, Ghana.
AJ
Dear AJ,
The spareness of your words is amusing. Our readership tends to be hungry for information, and your succinct entries just leaves them salivating for more. These are Water Striders, aquatic True Bugs that skate on the surface of ponds and other bodies of water, waiting for insects to fall in which they feed upon. Though Water Striders in the family Gerridae are quite common in North America and other places around the world, this posting represents a brand new category for our site that previously experienced a noticeable dearth of Water Strider images.
Reader Emails
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.
Letter 1 – Water Strider
Subject: Texas Pool Bugs
Location: Texas
October 28, 2013 8:07 am
please tell me what this thing is!!! have no clue
Signature: thank you TRay
Dear TRay,
We wish we had more photos of Water Striders on our site. They are amazing true bugs that spend their immature phase skating across the water in search of prey, especially insects that fall onto the water’s surface. When they attain adulthood, they are capable of flight.
Letter 2 – Water Strider from China
Subject: Water Strider from China
Location: Shijiazhuang, Hebei, China
August 5, 2017 6:21 pm
Dear Bugman,
what’s a common water strider in China? To be specific, Hebei Province. Is it the genus Gerris?
Thank you and kind regards,
Signature: Peter
Dear Peter,
You are correct that this is a Water Strider in the family Gerridae, but we do not have the necessary skills to further classify it to the genus or species level. According to BugGuide: “fine water-repellant hairs on the underside of the tarsi allow the bug to walk on water’s surface.”
Letter 3 – Water Strider: Countdown only Two more postings until 20,000
Subject: water striders
Location: Riverbend Park, Fairfax, Virginia
April 3, 2015 7:09 am
I found these water striders in a quiet part of a small stream going into the Potomac River in Riverbend Park, Virginia. They are clasping each other, but isn’t it a bit early for mating? If you can identify the species that would be great, too. Thank you for your wonderful site.
Signature: Seth
Hi Seth,
Thanks for sending in your wonderful image of a Water Strider, an aquatic insect that is able to disperse its weight so that it can skate across the surface of the water without breaking the tension.
Hi Daniel –
It looks like somehow you only got one of the water strider images I sent; here is the photo that may have gotten lost, showing one strider clasping another:
Regards, Seth.
Hi again Seth,
Thanks so much for forwarding what appears to be a mating or courtship image of a pair of Water Striders.
Letter 4 – Water Strider from Thailand
Subject: Bug from natural pool near Chiang Mai, Thailand
Location: Near Chiang Mai, Thailand
March 7, 2015 10:14 pm
G’day Bugman,
My wife and I were enjoying our honeymoon throughout SE Asia, and in one spot near Chiang Mai I came across an insect the likes I have never encountered before
Signature: John
Dear John,
This is a Water Strider in the family Gerridae, a group of insects that are also known as “Pond Skaters, Jesus Bugs, Water Skippers” according to BugGuide, a North American insect website. Water Striders skim across ponds and other bodies of water on long legs that distribute the insect’s weight so as not to break the tension of the surface of the water. Water Striders prey on insects that fall into the water. Here is an image from the Insects of Thailand site. We suspect your individual is immature as it does not have fully developed wings, but we cannot say for certain as we believe some species of Water Striders are wingless.
Letter 5 – Water Striders
More Water Striders
November 24, 2009
Hi Bugman,
I saw your comment about the dearth of water striders on WTB, so I thought I’d send these your way. The first one I’m pretty sure is Aquarius remigis based on images on BugGuide and its large size. According to BugGuide this is one of the largest and most common water striders in North America. The second one looks like something different though, based on the white markings on the thorax and abdomen. My best guess is something in the genus Gerris but there’s only one image on BugGuide that looks close. Both of these were found in August 2008, running around on Cascade Creek, Minnesota in large groups.
Joel Gardner (clickbeetle)
Cascade Creek (near Grand Marais, MN)
Hi Joel,
Thanks so much for your wonderful contribution of additional Water Strider images for our website.
Letter 6 – Water Striders
Subject: Water Striders
Location: Tucquan Glen, Lancaster County PA
October 29, 2013 10:36 am
Hi Daniel!
I read your comment about wishing you had more photographs of water striders. I attached a few shots that I took several weeks ago at Tucquan Glen in Lancaster County PA.
There are two shots of an adult with prey and a group of young individuals. They were not easy to photograph due to their constant motion.
Melody McFarland
Lancaster PA
Signature: Melody McFarland
Hi Melody,
Thanks so much for supplying some additional photos of Water Striders in the family Gerridae for our site. We see from the metadata on the digital image that your photos were taken on September 26, 2013. It appears that the adults do not have wings, so we thought they might be nymphs as well, but your individuals resemble this photo from BugGuide of a member of the genus Trepobates which BugGuide indicates: “Superficially resembles nymphs of Gerris. First antennomere shorter than three others combined.” Water Striders are perfectly adapted for skating across the surface of the water, and according to BugGuide: “fine water-repellant hairs on the underside of the tarsi allow the bug to walk on water’s surface; only the mid- and the hind legs are used for locomotion; they are attached to large coxae connected to the sides of the thorax and are unfit for walking on land.”
Alas, we haven’t the necessary skills to distinguish one species from another or even to definitively determine the correct genus, so our identification might be incorrect. Your photos which illustrate the feeding habits are a marvelous addition to our archive.
Letter 7 – Water Striders eat Leaf Hopper
Subject: What are these little water bugs?
Location: Boulder Colorado
August 1, 2012 8:24 pm
Hey Bugman!
I saw these little creatures today here in sunny Colorado in a small pool of water. At first glance they looked like some sort of fly that would stride on the water. While watching them for awhile longer, a leaf hopper jumped into the water and suddenly every one of these water flies swarmed it and devoured the leaf hopper! What are they?!
Signature: Michael Lohr
Hi Michael,
These are Water Striders in the family Gerridae. They are able to skate across the surface of calm bodies of water without sinking thanks to a wide leg span that disperses the weight as well as water repellent hairs on their legs. According to BugGuide, they are found “surface of temporary or permanent ponds, and slow-moving areas of streams and rivers” and they feed on “small living or dead insects on the water surface.” We are not certain if these are immature Water Striders or if they are just a very small species.
Letter 8 – Water Striders from Ghana
November 20, 2009
The following water bug pix were taken at Hans Botel Cottage, Cape Coast, Ghana.
AJ
Dear AJ,
The spareness of your words is amusing. Our readership tends to be hungry for information, and your succinct entries just leaves them salivating for more. These are Water Striders, aquatic True Bugs that skate on the surface of ponds and other bodies of water, waiting for insects to fall in which they feed upon. Though Water Striders in the family Gerridae are quite common in North America and other places around the world, this posting represents a brand new category for our site that previously experienced a noticeable dearth of Water Strider images.
Water do water skippers eat? Betty
We believe you want to know what Water Striders eat, but we are not certain. According to BugGuide they eat: “small living or dead insects on the water surface.”