Slugs mating looks like a slow, graceful "aerial ballet," where two slugs find an overhang, secrete a mucus thread, and hang upside down, twirling and entwining their bodies before everting their blue, translucent penises (from behind their heads) to exchange sperm in a beautiful, flower-like knot. This bizarre ritual involves them spinning as their reproductive organs interlock, transferring sperm before they separate, leaving a slime trail.
A pair of slugs climb a tree or wall to an overhang and suspend together head down from a 10–25 cm long mucus strand before everting their penises and exchanging sperm in mid air. Evolutionary explanations for this behaviour are unclear. Belocaulus angustipes mating with intromission and internal sperm exchange.
As the slugs dance they eventually intertwine and become excited. Both slugs insert their penises into the other slugs genital opening and take turns transferring sperm from one to the other. After much wriggling about and tugging the slugs separate and find an appropriate place to lay eggs.
Slug blood is called haemolymph and is a pale blue or grey colour. While vertebrates use iron to carry oxygen in the blood, which turns red when oxygen bonds, slugs use copper, which turns blue when carrying oxygen.
Food preparation prior to cooking can leave debris from which infection can also occur. It may be possible to become infected by consuming snail/slug slime (mucus) on produce or by transferring mucus from hands to mouth after handling snails/slugs.
What Is the White Substance Between Mating Slugs? If you spot two slugs close together in your garden, the white substance that you can see is slime or mucus. It plays a crucial role in attracting a mate. Also, in many species of slug, a lot of slime is produced during mating itself.
A mating ritual of the Leopard Slug (Limax maximus) is rarely seen and takes place mostly after Dark. I was hanging up string for a Hamach when I saw the event pictured below taking place and ran an got my camera and used flashlights to light up the scene.
They are apple snail eggs and they are an invasive species in addition to the eggs having a toxin in them so don't touch them with your hands!
Snail slime is a kind of mucus (an external bodily secretion) produced by snails, which are gastropod mollusks. Land snails and slugs both produce mucus, as does every other kind of gastropod, from marine, freshwater, and terrestrial habitats.
In the temperate climate of the PNW, mating typically is observed in the fall (Oct-Nov) and continues in the spring (Mar-Jun). When a slug matures, which can take approximately 5-6 months over the winter, it weighs more than 200 mg (up to 500mg) and now has the capacity to produce eggs.
Slugs are hermaphrodites, having both female and male reproductive organs. Once a slug has located a mate, they encircle each other and sperm is exchanged through their protruded genitalia.
After introducing the snails to each other, you can watch for signs of mating behavior. This may include the snails touching their tentacles or "dancing" around each other. Mating typically takes place at night, so you may need to observe the snails during this time. Wait for eggs to be laid.
Slugs are present from spring to fall, in cool, moist areas with shade. Slugs feed on leaves of many plants (especially seedlings), ripening fruits and vegetables, and decaying plant matter.
The simplest description is that slugs are snails without shells. Some of these mollusks do, in fact, have a shell, but those that do have internalized the shell and use it to store minerals.
Slugs are active for most of the year but are a particular problem in spring, when there's plenty of young growth for them to eat. They are mostly active after dark, especially when it's warm and damp. In hot, dry weather they bury themselves in the soil or hide in cool, dark places to avoid dehydrating.
Birds love to eat slug and snail eggs, so all you need to do is scatter them on the ground or, even better, on a bird table. There's no need to squash the eggs as birds will simply gobble them up whole.
The females prefer to lay these at night, so just check all the areas of the tank that are above the water level every morning. The clutches start off light pink to off-white in color and look like elongated masses of jelly bubbles (between 50-200 eggs in total).
By sleeping, snails can retain moisture and avoid excessively hot or dry climates. If the weather is unaccommodating, snails can sleep for three years straight. Depending on the geography, snails can turn to hibernation in the winter or estivation, called “summer sleep,” to avoid dry climates.
The mating ritual of slugs may appear bizarre, but it has evolved to fulfil both of these functions. Slugs are hermaphrodites. During intercourse, each suitor simultaneously delivers a packet of sperm to its partner's storage organ. To do this, they evert parts of their genitalia and lock them together.
Slugs on average have a life expectancy of about 12 to 18 months, but in some instances, they have been found to live for as long as six years.
This mucus is also used as the slugs navigation system, as slugs will find their way back to their tunnels and feeding sites by following their mucus trail.
It looks like your snail is releasing a stringy, yellowish-white substance, which is likely its waste or a byproduct of its digestion. Snails often expel long, stringy poop, and the color can vary depending on what they've been eating (like algae or leftover fish food).
Conclusions: Aestivating hanging upside down is a drought avoiding trait described here for the first time and is also a new function for the caudal gland mucus.