Humpback Whale Calves
Humpback whales become reproductively mature when they are between five and eight years of age. They mate during their winter migration to Hawaii, and eleven to twelve months later, upon their return to winter breeding grounds, the mother gives birth to a single calf. A fifty foot mother will give birth to a calf approximately fifteen feet long and weighing around two tons. The newborn instinctively swims to the surface within 10 seconds for its first breath. The mother begins feeding her newborn about 100 pounds of milk each day for a period of around six months, then the calf is sustained through a mixture of nursing and independent feeding for six months more. The mother’s milk is pink in color and exceptionally high in fat content (50%) which allows the calves to gain weight quickly. It is imperative for them to develop a thick layer of blubber prior to their 3,000-mile migration back to the cold Alaskan waters. After weaning, the calf has doubled its length and has increased its weight five times, attaining a size of about thirty feet and ten tons.
In Hawaii, humpback whales typically belong to groups consisting of two to three individuals for relatively short periods of time. The longest association between individual whales is when the mother cow, remains with her calf for a year during nursing. The mother generally never lets her calf stray more than a body length away for very long. They spend the first year or so of the calf’s life together, and the calf learns valuable survival lessons in this short amount of time, and is then weaned and separated. In many instances, cow and calf are accompanied by another adult known as an escort. Escorts can be of either sex, but are most often reported to be males, and remain with them for only a short time. Usually, a female humpback will bear one calf every two or three years, with an average life span between 40 and 50 years.
Hawaiian Shells and Shape
The mantle helps in the formation of the shell’s external features, such as ribs, spines, and grooves. For some species, these features provide protection from predators, added strength, or assist in burrowing. Shells of creatures like the nautilus have complex internal structures, such as multiple chambers containing water and gas that allow the creature to adjust its buoyancy. Most gastropods have coiled shells in the form of a logarithmic spiral, the only form of a coil that can both increase in size and retain its shape. Such an architecture is an efficient way to maintain strength while retaining the compactness of the shell. Some mollusks cement old discarded shells and other sea floor debris to their own shells. They use this technique as a means to camouflage themselves from predators, and to prevent sinking into soft sand or mud. While many mollusks have shells for protection from predators and environmental stresses, shells also have their disadvantages. Shells are permanent structures that mollusks must carry around for the rest of their lives, and its weight could slow the creature down. Some mollusks, such as the squid and octopus, have evolved by eliminating shells altogether.
Shell shape is a product of evolution which is greatly influenced by local environment and type of sea floor. A shell that is low and wide might indicate strong waves or many predators. A thinner, more spherical shell probably comes from deep water, or areas around the north and south pole that are poor in calcium (unlike rich tropical waters). On hard sea floors, crawling gastropods have coiled shells or flat, saucer-like shell cases that allow them to retreat into the shell when in danger. On a sandy or rubble strewn surface, shells have expanded shell edges that help stabilize the mollusk with its opening facing down. In calmer waters, sculpted features such as spines increase the volume of the shell, making the mollusk look more formidable against predators. This also increases the surface area of the shell, allowing other marine organisms to settle on the mollusk’s shell surface, serving as a physical and chemical camouflage. For burrowing in soft muddy or sandy surfaces, some mollusks have evolved smooth, long, tapering shells. Many molluscs are able to withdraw far enough into their shells to be beyond the reach of predators. Others are able to block their apertures with a hardened plug called an operculum.
Environmental changes, injuries, or abnormal conditions of the mantle are often reflected in the shell they form. When the animal encounters harsh conditions which limit its food supply or otherwise cause it to become dormant for a while, the mantle often ceases to produce the shell substance. When conditions improve again and the mantle resumes its task, a ‘growth line’ is produced extending the entire length of the shell. Patterns and colors on the shell after these dormant periods are sometimes quite different from previous colors and patterns. Each species of mollusk will build the external shell in a genetically predetermined shape, pattern, ornamentation, and color, while at the same time, giving itself a look all its own.
Hawaiian Shells and Formation
Appreciation of a shell’s beauty can only be enhanced by understanding a shell’s formation. The blood of a mollusk is rich in a liquid form of calcium. A soft, outer organ called the ‘mantle’ concentrates the calcium in areas where it can separate out from the blood, forming calcium carbonate crystals. The mantle continues depositing sheets of the crystal in varying thickness, shape, and orientation. Adjacent layers are often deposited with their crystal planes at right angles to each other greatly increasing the strength of the shell. The shell grows as the animal inside adds its building material to the leading edge near the opening. This causes the shell to become longer, wider, and stronger to better accommodate the growing animal inside.
The mantle orchestrates the designs and colors of the shell. Production of new shell material is influenced by several factors: sexual hormones, intrinsic rhythms, diet, acidity and temperature of water. Colors in shells are derived from organic pigments found in their food. Glandular cells collect these pigments, mix them with fluid calcite, and set this substance into the outer shell before it hardens. There are four main pigments that produce the many colors seen in shells: yellow carotenoids, black melanins, green porphyrins, and blue and red indigoids. Most color cells are located along the front edge of the mantle where new shell material is added. A straight color line or ray is formed when the color cells remain in the same position as the shell grows out. If color pigment production continually starts and stops, a pattern of dots or dashes is drawn on the shell. If the color cells actually migrate to one side, a slanting trail of color is produced. Other kinds of behavior by color cells can produce circles, triangles, and other shapes. Mollusks within a particular species have basic colors and patterns that are genetically inherited, but natural variation, like different hair color among people, gives each shell a character of its own.
Orchid Vanda Care
Vanda (pronounced VAN-dah) orchids are mostly warm and full sun growing plants with colorful flowers, including blue, red, orange, and yellow. Originating in tropical Asia, they are easily grown in warm climates, and the show from one spike can last for eight weeks or more, and vigorous plants, can often bloom twice a year.
Vanda Light
They enjoy full sun in the morning and afternoon, but shading at mid day. Their leaves should be a light green color, and a darker green color indicates too little sun.
Vanda Temperatures
Temperatures for this orchid should be warm and humid for optimum plant growth. The ideal day temperature is 75-85 degrees F., while the ideal night temperature is 65-75 degrees F. Warmer temperatures mean faster growth, which must be balanced with higher humidity, air movement, and increased water and fertilizer.
Vanda Water
These orchids are epiphytes in nature, and are used to drying out between the rains of their natural habitat. Water should be applied copiously when the plants are growing, but the roots must dry quickly.
Vanda Humidity
A high humidity is essential during the growing season, from early spring through late fall. Humidity of 80 percent is ideal. Air movement must be strong.
Vanda Feeding
Fertilize with a balanced fertilizer applied at one-quarter-strength solution at every watering. Use a high-phosphorus fertilizer every third application to promote flowering.
Vanda Potting
Potting should be done in the spring every two to three years, or when the potting medium begins to deteriorate.
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Orchid Tolumnia Care
Tolumnia (pronounced toh-LUM-nee-ah) orchids are endemic to the Caribbean Basin with many confined to a single island. The foliage is usually 6 to 12 inches in height with miniature pseudobulbs bearing fan shaped leaf rosettes. They produce a shower of blooms 2 to 3 times a year of bright colorful blossoms ranging from bright sunshine yellows and golden browns, to vibrant reds and oranges. Their petite size and ability to adapt to a fairly wide range of conditions make them suitable for growing in small spaces.
Tolumnia Light
Bright, diffused light is preferred. Plants that are growing well but reluctant to bloom usually need an increase in light intensity.
Tolumnia Temperature
The temperature range for these orchids should mimic the Caribbean. The optimum range is 80 to 85 F during the day and 65 to 70 F during the night. Avoid prolong exposure to temperatures below 60 F or above 90 F.
Tolumnia Water
These orchids have no large pseudobulb water reserve, and must be watered well then allowed to dry out by night. The adage “if in doubt, don’t water” applies here.
Tolumnia Humidity
The humidity should be above 60%, and a good air movement must be provided so that they dry out between misting.
Tolumnia Feeding
Frequent and dilute feeding is the preferred approach using a balanced fertilizer applied every other watering at one quarter strength. Flushing with plain water once a month is important because residual salts can damage the roots.
Tolumnia Potting
The proper combination of good irrigation, adequate aeration, and rapid drying of the roots is key. Repotting should be done when new growth begins in the spring every two to three years. Mounting with twigs, cork bark, or small wood is the method of choice. They will also do well in tiny pots filled with loose charcoal, small orchid bark, or any other fine material.
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