Lawn shrimp, also known as Browne’s blechum, may be an unwelcome guest in your yard. These tiny creatures can become a nuisance, and it’s essential to address the issue before they cause significant damage to your lawn or garden.
Getting rid of lawn shrimp involves understanding their habits and implementing measures to prevent their proliferation. In this article, we will discuss various methods to help you maintain a healthy, shrimp-free lawn. As we explore different techniques, we will also consider their pros and cons, ensuring you make the best decision for your specific situation.
Understanding Lawn Shrimp
Lawn Shrimp Characteristics
- Color: Pinkish-brown
- Size: Small, less than 1 inch
Lawn shrimp, or terrestrial amphipods, are small crustaceans native to Australia, New Zealand, and the UK. Known for their pinkish-brown color, these amphipods resemble tiny shrimp. They are often found in moist areas, and after heavy rain, they can appear in large numbers in garages and under house doors.
Habitat and Distribution
- Moist Areas: Ground cover, leaf mold, garages, under house doors
- Countries: Australia, New Zealand, UK, California
These crustaceans typically live on the surface of mulch and moist ground, up to a depth of 13mm. They thrive in soft ground cover and leaf mold, particularly beneath shrubbery. Lawn shrimp are now widely distributed, including California, where they have been introduced.
Relation to Other Crustaceans
|Slender, nearly transparent||More robust||Slender, slightly transparent|
|First 2 pairs of legs have pincers||First 3 pairs of legs have pincers (1st pair large)||First 2 pairs of legs have pincers|
|Tail flattened side to side||Tail rounded||Tail fan-like|
Lawn shrimp belong to the Arcitalitrus sylvaticus species and are closely related to other crustaceans such as crayfish and regular shrimp. They share some characteristics with both, including their overall shape and the presence of pincers on their legs. However, unlike crayfish, their tail is flattened side to side, and they have a more slender and nearly transparent appearance.
Lawn Shrimp Behavior and Impact
Lawn shrimp, also known as terrestrial amphipods, feed on various organic materials. Some examples include:
- Decomposing plant debris
- Dead leaves
- Fungi, such as mushrooms
They mainly thrive in moist environments and can often be found in areas with damp soil, such as gardens, wet lawns, and leaf litter.
Reproduction and Population Growth
Lawn shrimp reproduce quickly, which can lead to a significant growth in their population, especially in wet conditions. For example, conservancy fairy shrimp found in vernal pools can hatch and mature within 37 days. Their rapid reproduction can sometimes cause an infestation, becoming a nuisance to homeowners.
Lawn Shrimp vs Conservancy Fairy Shrimp Reproduction:
|Attribute||Lawn Shrimp||Conservancy Fairy Shrimp|
|Maturity Time||Rapid||37 Days|
|Ideal Conditions||Wet, damp soil||Vernal Pools|
Role in Ecosystem
Despite being harmless to plants and humans, lawn shrimp are an essential part of the ecosystem. Some key roles include:
- Decomposing organic matter, promoting healthy soil
- Serving as a food source for various predators, such as birds and small mammals
However, in large numbers, they can become a nuisance for homeowners, often entering garages or homes when seeking moisture.
To summarize, lawn shrimp are small, harmless crustaceans that can become bothersome due to their feeding habits and rapid reproduction. As part of the ecosystem, they play crucial roles in breaking down organic materials and providing food for other organisms.
Managing Lawn Shrimp Infestation
Physical Removal Methods
Lawn shrimp, also known as amphipods, can be a nuisance in damp areas of your yard. To get rid of them, try these physical removal techniques:
- Vacuuming: Use a vacuum to remove lawn shrimp from surfaces, such as patios or decks.
- Sweeping: Sweep them away from your home’s entrance during dry spells.
- No chemicals required
- Immediate results
- May not eliminate the entire infestation
Using Chemical Solutions
In some cases, you might need to resort to chemical solutions. Two options include:
- Insecticides: Apply a pesticide that targets lawn shrimp, ensuring it’s safe for pets and plants.
- Diatomaceous earth: This natural substance can be sprinkled around damp areas to deter and kill amphipods.
- Effective for larger infestations
- Can provide long-lasting control
- May pose risks to non-target organisms
- Can be harmful if not used correctly
Preventing lawn shrimp infestations requires proper yard management. Focus on these key points:
- Reduce dampness: Limit overwatering and improve drainage to keep topsoil fresh and dry.
- Remove organic matter: Regularly mow your lawn and remove wet leaves, as these environments attract amphipods.
- Mulch management: Ensure mulch is not overly damp and aim for a depth that does not exceed 1/2 inch.
By following these guidelines, homeowners can minimize the chances of dealing with a persistent lawn shrimp issue.
|Physical Removal||No chemicals, immediate results||Time-consuming, not always 100%|
|Chemical Solutions||Effective, long-lasting control||Harmful if misused, kills others|
|Preventive Measures||Sustainable, safe for all||Requires regular maintenance|
Ensuring Lawn Health and Protection
Maintaining Proper Yard Management
Short and frequent watering can lead to shallow root systems in plants, which is not ideal for lawn shrimps. Instead, focus on deep watering, which promotes a healthy lawn and keeps the pests at bay. Maintaining your lawn well-mowed and clean can also discourage lawn shrimps from taking up residence. Examples of good yard management include:
- Removing excess dead leaves, debris, and decaying plants
- Retaining proper light penetration by trimming overgrown plants
- Reducing excess moisture through proper drainage systems
Attracting Natural Predators
Introducing natural predators of lawn shrimps, such as birds and fish, to the area can help keep their numbers under control. Some examples of predator-friendly features for your lawn are:
- Bird feeders or houses
- Pond or water feature for fish
- Avoiding use of harmful chemicals that can harm predators
|Lawn Management Techniques||Benefits for Lawn Shrimp Control|
|Deep Watering||Discourages shallow root systems|
|Clean & Well-mowed Lawn||Less attractive environment|
|Proper Drainage||Reduces excess moisture|
Remember that prevention is key. By taking care of your lawn, minimizing the use of chemicals, and maintaining balance with natural predators, you can create an environment where lawn shrimps are less likely to flourish, giving you a healthy and protected lawn overall.
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 – Lawn Shrimp from UK
weird jumping bug
Location: UK (Cornwall)
March 17, 2012 8:54 am
Seen this in the garden for the last few years (once disturbed, they jump about, somewhat clumsily). As you can see, they look almost marine-like.
Your terrestrial amphipod, Arcitalitrus sylvaticus, has many marine relatives. The species was accidentally introduced to various parts of the world from Australia, including “New Zealand, the British Isles, Florida and California” according to BugGuide. These creatures proliferate in well watered gardens and they are commonly called Land Shrimp or House Hoppers. The frequently enter homes during heavy rains, though they quickly dry out and die indoors.
Letter 2 – Lawn Shrimp from Australia
What’s this bug?
Location: Sydney, Australia
December 23, 2010 10:20 am
I live in Sydney, Australia. We’ve been getting these bugs under our sofa but have never seen a live one. Usually notice them on the tiles in the morning. They’re about 5-10mm in length.
This is a Lawn Shrimp or House Hopper, a terrestrial Amphipod that often enters homes after a heavy rain. Your letter is of especial interest to us as Australia is the native habitat of the Lawn Shrimp. The species has been introduced to other regions including southern California and in the past week, because of the heavy rains in the area, we have been inundated with identification requests from California where the species is considered to be an introduced annoyance.
Letter 3 – Lawn Shrimp appear with California rains
Subject: Unknown Bug
Geographic location of the bug: California Coastal
Time: 12:26 PM EDT
Your letter to the bugman: Hi,
I keep finding these bugs dead on my floor. I opened some boxes from overseas so that my be where they came from.
How you want your letter signed: Simon
You are correct that this Terrestrial Amphipod, commonly called a Lawn Shrimp or House Hopper, is from oversees, however, we do not believe it came from your boxes. Lawn Shrimp have been reported in Southern California for many years. According to BugGuide, their range is “Southeastern Australia (New South Wales and Victoria), as well as nearby areas of the Pacific, but introduced into New Zealand, the British Isles, Florida and California” and “Non-native; introduced probably from Australia along with blue-gum eucalyptus trees in the 1800s. First recorded in San Francisco, CA in 1967.” They are not usually noticed until we have soaking rains and they seek shelter from the water-soaked ground. BugGuide notes: “These are rarely seen except when flooding or lack of moisture forces them to abandon their home in the soil in search for suitable conditions. At such times they often end up dieing on pavement or in homes and become a nuisance. Once they start appearing, there’s not much that can be done except to sweep them up- pesticides are pointless, bcause by then they’re already dying or dead.”
Letter 4 – Lawn Shrimp from South Africa
Location: Johannesburg, South Africa
December 24, 2010 5:59 am
We find a lot of these dead bugs in my entrance hall every morning. The only one that was still alive was battling to walk, flopping over, before it died. They look like an overgrown flee or a type of prawn. We live on the side of a high hill.
Signature: Maurae Wooding
This is a Lawn Shrimp or House Hopper, a terrestrial Amphipod that is native to Australia, but which has been introduced to other regions including South Africa, New Zealand, Florida and California. They can become quite plentiful in cultivated gardens where they go unnoticed, but after a heavy rain, they seek dry shelter, often indoors, where they promptly die and come to the attention of the human residents. Though they are a nuisance when they enter the home, they are basically a benign species.
Thank you so much, that really explains exactly what we are seeing.
We have been having a lot of rain lately especially at night and have had a lot of millipedes, centipedes and earth worms coming in due to the wet but those are all still alive so we can rescue them and return them to a drier spot in the garden, I could not understand why the Lawn scrimps were all dead or dying.
Thank you for a wonderful website and your quick and helpful response.
Letter 5 – Lawn Shrimp found in South Carolina
aSubject: Hopping Bug
Location: Bluffton, SC
May 21, 2016 4:28 am
What are these hopping bugs that have come out at night under my porch light? The next morning a lot of them have died. These are in Bluffton SC .
Signature: R McLain,
Dear R McLain,
This looks and acts like a Lawn Shrimp or House Hopper, Arcitalitrus sylvaticus, a species described on BugGuide as being from “Southeastern Australia (New South Wales and Victoria), as well as nearby areas of the Pacific, but introduced into New Zealand, the British Isles, Florida and California” and preferring habitat that is “Moist soil and organic matter within 13 mm of the surface, often among ivy or other ground covers, mostly eucalyptus. Their exoskelton has no waxy coating to keep moisture in, so they can’t survive dryness. They drown in water, though, so they need continuously moist, but not waterlogged conditions.” Based on this BugGuide posting, they are spreading from Florida to nearby Georgia and your posting indicates they have now spread north to South Carolina.
Thank you Daniel. I thought they resembled shrimp!
Lawn Shrimp and true Shrimp are classified together as Crustaceans in the same subphylum.
Letter 6 – Lawn Shrimp
Client Thinks this is a large flea
Location: San Jose, California, USA
December 29, 2010 4:36 pm
HI and thanks for your help. I work at a veterinary clinic and a client e-mailed us this picture thinking it might be a giant flea. We know it is not a flea, however can you help us identify what it is? We are in San Jose, California. This was found in the house half dead on 12/28/2010.
Signature: Samantha, Front-office manager
This is a Lawn Shrimp or House Hopper, an Australian terrestrial Amphipod that has been introduced to California. They thrive in cultivated gardens that are well watered, however, when there are flooding rains, which California has experienced in recent weeks, they often seek shelter indoors where they promptly die of dessication. They will not harm pets or furnishings, but when the die indoors in large numbers, they are a real nuisance.
Letter 7 – Lawn Shrimp emerge with the rains
Subject: Dead bugs outside door?
Location: Huntington Beach, ca
December 7, 2014 8:56 am
We woke up today with a bunch of small brown bugs with pincars. Just by back door outside all dead. Can you let me know if they are something we should be concerned about?
The presence of Lawn Shrimp, Arcitalitrus sylvaticus, in the landscaping generally goes unnoticed until we have a good rain that soaks the ground, at which time they often emerge in alarming numbers, dying on the concrete or entering homes to die. Lawn Shrimp are native to Australia and they are also known as House Hoppers. See BugGuide for additional information on Lawn Shrimp.