1. Describe the methods used to study marine mammal movement

   1. Identify which natural markings are used for different species

Indirect : inferred from distributions

• More blue = more whales

• Less blue = less whales

• The whales move seasonally between locations

Direct : repeated observations of individuals

• If the same whale is spotted at two locations, you know it is moving

1. Tags & Branding

   1. Bottlenose dolphins tags are quite invasive and leave behind holes as the tag falls out

   2. The number is a branding tag

2. Natural markings 

1. less invasive

2. an alternative for tags & branding

1. started with manatees 

1. Manatees

   1. any types of scars on their bodies are used to identify them as it is unique to each individual in mid 1950s

   2. Then in the 1960s, they did the same with humpback whales but used the undertail of the fluke, as the fluke pigmentation is unique to each individual 

   3. It is also different in the northern and southern hemisphere

2. Sperm whales 

   1. have fully black tails, so instead they used the shape of the fluke (fluke serrations/notches) to distinguish between them

3. Right whales 

   1. have perfect tail flukes, so researchers came up with the idea to use the white patches on them called the callosities to identify it

   2. Callosities : a thickened or hardened part of the skin (a callus)

4. Orcas 

   1. use the saddle patch (white areas on the back) that are unique to each orca

5. Bottlenose dolphins 

   1. use the shape of the dorsal fins and any notches from boat strikes

6. Grey seal

   1. the fur pattern of the females is distinctive so the brown patches are used to distinguish between them

       c.    Genetic Tagging

Genetic Tagging : collect DNA by using biopsy and send the data back and forth for analysis

1. can also tell the sex of the animal, and can be used for paternity determination as well

       d.    Telemetry : tags that transmit data in real time → almost like live tracking

1. It was really invasive and larger but now it is developed to be smaller and less invasive

2. Still costly and invasive

   1. Most researchers can only put out a few tags because sometimes they are lost

1. Polar bears

   1. collar

2. Seals 

   1. Transmitter is stuck on skin

3. Manatee

   1. band is placed around tail the transmitter or tag attached to it

4. Dolphins

   1. attach it to their dorsal fin

2. Identify and discuss the major factors driving movement patterns

Migration : repeated large scale movement between two areas within the home range of the animal

• Migration usually looks like a persistent linear movement

• Between feeding and breeding grounds

Dispersal : one time permanent movement

• indicates that they are leaving their home range

• Reason → inbreeding avoidance

Movement is costly as it requires energy to move

• have evolved to meet their daily needs

• Happens at different spatial and temporal ranges

• The blue oval represents the home range of the animal

3. Differentiate among the different scales of marine mammal movement

Migration : repeated large scale movement between two areas within the home range of the animal

• Migration usually looks like a persistent linear movement

• Between feeding and breeding grounds

Dispersal : one time permanent movement

• indicates that they are leaving their home range

• Reason → inbreeding avoidance

Movements : Spatial and Temporal Variation

1. Diurnal and Tidal

Diurnal : of or during the day

• Focus on daily movement pattern

1. Hawaiian spinner dolphin

   1. have a daily schedule

      1. Day → They come really close to shore and are trying to sleep, need a shallow sandy bottom to rest during daylight

      2. Night → Forage on the deep scattering layer

      3. The deep scattering layer rises higher at night and is deeper during the day

         1. During the day they have to dive deeper and require more energy so instead they forage at nighttime

Tidal pattern : The alternating advance and retreat of seawater along a coastline

• usually happens twice a day on average

1. The humpback whales move up as the tide come in and get a lot of food from it as the prey species move along it too

2. As the tide move back out, the dolphins move back with it as the water is now shallower

1. Seasonal Pattern

   1. Humpback whales

   2. Primarily forage close to poles in cold areas

   3. All the blue locations are where these populations are known to feed

   4. Feed during summer months

   5. Green areas where they spend their winter months and move to warmer water for breeding purposes

WHY DO WHALES LEAVE ALASKA?

• They ran out of food

  • the food is not coming back

• The blubber layer keeps them warm

  • if there is no food, the blubber layer will become thin as you will be fasting

  • rather move to warmer water to stay comfortable

• The red dots : Arabian sea humpback whales is the only known population that does not migrate

  • These waters are nutrient dense all year around so they don't move

  • Problem is there is lot of development in that area so now this population is in critical danger as of now

4. Compare methods used to assess home range

5. Describe the main reasons that marine mammals migrate

1. Breeding

2. Molting

3. Predator Avoidance

Migration : Breeding

• Aggregations often form during breeding seasons 

• Site fidelity to breeding areas varies 

• Cetaceans : most lack specific breeding areas

  • EXCEPTIONS : humpback, gray and right whales

• Right whales (left map)

  • Southeast US coast 

  • Florida → Southern Scotian Shelf

  • Movement between calving grounds in fall/winter along SE coast and feeding areas around Cape Cod

• Gray whales (center map)

  • West coast of US

  • Baja Mexico → colder waters of alaska

  • Movement between southern winter feeding grounds and northern summer breeding grounds

• Pinnipeds : finer scale fidelity

  • Show really strong site fidelity

  • Coming back to same exact location every year

    • Down to the portion of the beaches that they were born

    • Mothers will go to the beach they were born to give birth 

  • Males choosing within 55m of previous site

  • Females choosing within 50m of previous site 

  • Spatial distribution based on prior location 

Other Factors : 

1. Molting

   1. Molting is different between phocids and otariids 

      1. Phocid → annual molt

         1. catastrophic molt

         2. Lose large patches of fur and skin

            1. Haul out on beaches because air is a better insulator

            2. they have to pump blood to surface of skin to accelerate the replacement of skin and fur

            3. Cetaceans 

               1. Move to warmer waters where it is safer to molt without worrying about thermoregulation 

2. Avoidance

1. predators/disease

   1. Juveniles at risk for predation

   2. Whales might move to get away from orcas

      1. Moms and calves follow california shoreline very closely instead of a straight line up the coast 

      2. Less likely for the orcas to come in due to human activity 

         1. Safer but longer route

   3. Humpback whales move to places where orcas are less present 

2. Thermoregulation

   1. Whales undergoing migration are fasting

      1. Starving internal parasites

      2. Start over healthier

         1. Does not apply to arabian sea whales because they are not migrating

   2. Calves born without blubber layer are more susceptible to hypothermia, body has to work a lot harder to keep them warm

      1. Mom has to feed them excessively to build up blubber layer

         1. Even if the calf could survive colder waters, this would be such a high energetic cost to the mom

      2. Giving birth in warmer layers prevents them from having thermal stress right after they are born and makes the transition easier while they build their blubber layer

      3. Temperature seems to drive migration location for birthing reasons

   3. Sirenians

      1. Springs have year-round temperature of 72 degrees

      2. Migrate to springs in large numbers to assist with thermoregulation 

      3. Also thermal refuges like outside of power plants where warm water is pumped out

         1. Usually doesn't have an adequate food supply so they are fasting because it is more important for them to thermoregulate

6. Define population and describe the difficulties in identifying population boundaries

Population : group of interbreeding individuals of the same species

• Same place, same individuals, same time

• Two populations can also overlap and mate 

• Separate population = not mating

How do you define the boundaries?

1. Biological → using some criteria that are measurable and meaningful to the animals themselves

   1. Genetic  and behavioral data

2. Political → state/national boundaries, based on arbitrary lines that humans have created

   1. Bottlenose dolphins that live off the east coast of the US 

      1. Northern migratory (NJ→NC)

      2. Southern Migratory (FL→VA)

      3. Resident stocks 

      4. East Australian Whales being hunted in Antarctica by Japanese when they enter international waters

3. Practical → Manageable from a conservation perspective

   1. NOAA fisheries

   2. Set boundaries on a small enough scale that they can manage them

7. Compare/contrast methods used to determine population abundance

   1. Identify the assumptions of each method

Methods for Determining Abundance

1. Census : accurate and complete count of individuals 

1. Trying to count marine mammals accurately is almost impossible because they are moving and largely out of site

2. Easier for species that haul out on land for periods of time 

   1. Walruses on breeding beach

   2. Can take aerial photos and count them individually → could get relatively accurate count

       2.   Index count : counting a sample of individuals 

1. Trends only

2. Not all individuals migrate/move through a channel at the same time or in the same way in areas where an index count is being taken 

   1. Example : mothers and calves move closer to shoreline, might miss others in the population that are not as visible 

3. Useful in collecting trend data → is it increasing or decreasing from year to year?

4. Common for citizen science projects

        3.   Estimates → count sample and extrapolate to population 

1. Counting a sample, but the sample has to represent the entire population 

   1. Can't just be a subset of an age/sex of population 

2. Line transects (distance sampling)

3. Mark-recapture

Line Transects (Distance Sampling)

• Survey large areas (by ship or aircraft)

• Set up lines systematically 

  • Gap between them must be the same, but not so large that you can’t see from one transect to the other

  • Orientation changes what your data looks like

• Count the number of animals and spatial arrangement around line 

  • Document where it is allocated and how many individuals there are 

  • (Theta) = angle between vessel and individual 

  • R = distance from vessel to individual 

  • X = exact distance from animal to transect line at that particular location

Line Transects : Assumptions 

1. Sample has to represent population 

   1. Transects must make sense 

      1. Insert graphic

      2. Lines perpendicular to shoreline so they are equally likely to catch an individual 

2. No missed animals on transect line

   1. Adjust speed so that you are unlikely to miss those individuals 

   2. Will probably still miss some, but adjusting speed to be more precise makes missing them less likely 

3. Animals do not move prior to detection 

   1. If they are moving fast and in a direction opposite of the transect lines, you are likely to miss them

4. Data recorded accurately

5. Observations Independent 

Mark Recapture 

• Useful when populations aggregate 

  • If you're studying a large whale species, you're more likely to watch mark recapture in breeding or feeding grounds, but not migration between the two 

• Individual specific data 

• Sample (N1) - “captured” → marked → released 

  • Better to use natural markings on individual

    • Humpback whales (fluke pigmentation patterns)

    • Bottlenose dolphins (damage to dorsal fins)

• Sample (N2) - “captured” → of which M2 already marked 

• Proportion of marked vs unmarked used to estimate population size 

N = N2/M2

Mark-Recapture : Assumptions

1. Marks are unique 

   1. No 2 individuals could look the same 

   2. Nuanced differences 

2. Marks cannot be lost 

   1. Whatever the feature you’re using, it cannot be lost over time 

   2. Record accumulating or changing marks over time

   3. Example : bottlenose dolphins dorsal fin will not grow back portions lost by accidents or boat strikes

3. All marks are correctly recorded/identified

   1. Could influence your population estimates if you are incorrectly identifying individuals 

4. Marking does not affect survival or future catch-ability

   1. Bolting tags, freeze-branding, etc., can cause health consequences or change behavior patterns

      1. Avoid research vessels

      2. Avoid areas they were tagged or captured in 

5. Equal probability of capture within each sample

   1. If not all individuals are in the area seasonally, you must space your surveys closely together so you're not losing individuals and getting an accurate count 

   2. Within the same season 

Other Uses of Mark-Recapture

Movement patterns → home ranges and site fidelity 

Life history and population dynamics

2. Survival and reproductive success

3. On a population and individual level 

8. Describe the main demographic parameters used to assess population dynamics

Population Dynamics

Demographic parameters : how and why abundance is changing in a population 

1. Natality (births)

   1. Collective birth rate for all of the females in the population

      1. Calculating the potential birth rate (not an exact number)

   2. How many females are there, and how many are reproducing each year

   3. Positive influence in population size 

2. Mortality (deaths)

   1. Negative influence on population size

   2. BR > DR → increase in pop. size

   3. DR > BR → decrease in pop. size

3. Immigration and Emigration (dispersal)

   1. Immigration → entering a population (positive effect)

   2. Emigration → leaving a population (negative effect) 

N = (B-D) + (I - E)

Population Size → Why count?

Abundance 

1. How many animals are there and is it a viable population?

Trend 

2. Is abundance count stable? Increasing? Decreasing? Unknown threats affecting populations?

Life History → factors that define how an animal grows/reproduces/dies

3. Indirect information related to abundance

4. Related to pop size in trying to keep it stable, but also an indicator of how well a population is doing 

5. East Australian whales giving birth annually because population is so low 

   1. Huge energetic and health cost

Management Success → counting how many animals are in a population to understand if your management decisions are working they way you thought they would 

6. Hawaii closing bays to human activities so spinner dolphins can rest

   1. Finding out if time/area based closures are working

9. Explain how intrinsic growth rate (r) and carrying capacity (K) are related to population growth

Population Growth : Exponential vs. Logistic

Intrinsic growth rate (r) : maximum rate of growth when no environmental factors are limiting the population increase 

1. No competition

2. Adequate shelter 

3. Unlimited resources 

4. Etc. 

   1. If a population is functioning under all these assumptions, it is experiencing exponential population growth 

   2. Leveling off of population is logistic growth, where the population size reaches a relative maximum # of individuals for the resources in their area 

      1. Just enough resources for everyone (carrying capacity)

Carrying capacity (K) : max number of individuals that a habitat can support

Exponential growth : when resources are unlimited, populations exhibit exponential growth, resulting in a J-shaped curve

Logistic growth : slowing down and leveling off at carrying capacity

• Don't worry about knowing those equations, but be able to understand them and what they mean on the graph 

r vs K Selection Theory 

K - strategists : evolved to maintain relatively stable population sizes and do not exceed the carrying capacity of their environment/species 

Ex : large carnivores, whales, elephants, etc.

r - strategists : species that typically live in unstable and unpredictable environments with population sizes that vary between well below or above carrying capacity

Ex : bacteria, insects, annual plants, etc.

Fecundity : # of offspring a female is able to produce in her lifetime

Density-Dependence 

As a population nears carrying capacity, we expect (in this order) :

1. Increase in juvenile mortality 

   1. Juveniles are most vulnerable and less experienced to compete for resources

   2. Smaller size

   3. First ones to experience stress when the population reaches carrying capacity 

2. Increase in age at sexual maturation

   1. Reproduction is energetically costly

   2. In order to successfully carry a pregnancy and produce milk, they need an abundance of food

   3. Limited resources will stunt developmental growth and push back typical agge of sexual maturity

3. Decrease in fecundity

   1. Fewer offspring in lifespan because resources are limited and need longer to recoup between births 

   2. Also due to (b)

4. Increase in adult mortality 

   1. If resources are still limited at this point, individuals that are weaker, older, sicker, not as good competitors will start dying off earlier than they normally would in a stable population 

Carrying capacity : the maximum population size of a biological species that can be sustained by that specific environment, given the food, habitat, water, and other resources available

10. Distinguish between exponential and logistic population growth

Exponential growth : when resources are unlimited, populations exhibit exponential growth, resulting in a J-shaped curve

Logistic growth : slowing down and leveling off at carrying capacity

• Don't worry about knowing those equations, but be able to understand them and what they mean on the graph 

11. Identify the (reproductive) Life History Traits that directly influence population growth

Life History Characteristics 

1. Growth

   1. Once you have reached full body size, that energy is moved to maintenance and reproduction 

2. Maintenance

3. Reproduction 

1. Large body size →

   1. Long life-span 

   2. Slow growth and delayed sexual maturity 

   3. Produce few offspring and invest heavily in each

2. Reproductive LH traits → Natality 

   1. Age of sexual maturity 

   2. # of offspring per reproductive cycle

      1. Polar bears are the only marine mammals known to have twins

   3. Frequency of reproduction (Gestation length and IBI’s)

      1. IBI(interbirth interval) : the day that you give birth to one offspring → the day you give birth to the next offspring 

      2. In most cases with most marine mammals, there will be a longer IBI than gestation length because they are investing heavily in each offspring 

      3. Example : 

         1. Takes 11.5 months to grow calf

         2. IBI : 3-6 years

4. Reproductive lifespan (senescence?) : age at which you reach sexual maturity to the age at which you stop reproducing (?)

   1. If there is no defined menopause → they are reproducing up until the point that they die

Life History traits vary within and between populations → they are NOT fixed

12. Define bimaturism and provide examples of the three patterns

    1. embryonic diapause and explain why it occurs

Bimaturism : sex difference in age of reproductive maturity

1. Males mature later

2. Females mature later

3. Males have delayed social maturity

Density dependent – populations with low density mature earlier

3 general patterns of bimaturism—not constant with species or time—can fluctuate.  

1. Males maturing later is most common in polygamous species--beneficial because when competing with other males, having a larger body size makes them a better competitor with more time to grow to maturity. Sperm whales, bottlenose dolphins in shark bay, manatees (males at 9-10).  

2. Females maturing later—relatively rare. Occurs in dugongs. Females are more successful at giving birth and keeping their calf alive with a larger body size. Males don’t compete the same—they perform scramble competitions where males free roam in search of a fertile female.  

3. Physiologically, males and females can reproduce at the same age, but males do not attempt until later. Comes down to the intense male-male competition. Primarily seen in mysticetes.  Also seen in pinnipeds—elephant seals—wait it out because more probability of being successful and surviving

Embryonic diapause (delayed implantation) : the temporary suspension of development of the embryo

1. Majority of species have a seasonal breeding pattern, especially for those that migrate

2. Those with gestation lengths shorter than one year have embryonic diapause (delayed implantation)

   1. After mating occurs, the zygote implants but there is a pause in the development of the embryo

   2. Allows females to stay on an annual cycle and give birth at the appropriate seasonal time

   3. Implantation occurs when molting occurs

   4. If this was absent, they would give birth during foraging season

13. Compare/contrast the maternal care strategies of marine mammals

Maternal Care Strategies : 

1. Fasting → Phocids & Mysticetes

2. Foraging Cycle → Otariids & some Phocids

3. Aquatic Nursing → Odontocetes, Sirenians & Odobenids

Maternal Care Strategies 

• Lactation strategy linked to other aspects of maternal care

1. Fasting

   1. Rare in terrestrial but normal in marine mammals

   2. Mom is not eating, limit to how long she is physically capable of providing top quality care

2. Foraging 

   1. Mom feed while pup fasts and then mom fasts while pup feeds

   2. Typical of otariids and some smaller phocids

      1. If you don't have a large body size, you don't have the fat preserve for fasting

      2. Foraging cycle provides balance

   3. Downside : pup is completely vulnerable in the weeks that mom is out foraging

3. Aquatic Nursing

   1. Follow mom everywhere, she can eat when she needs, and calf/pup feed when they need to 

14. Explain the relationship between lactation duration and other features of maternal care

Less lactation time = less time for milk and knowledge transfer

Lactation/milk content :

Fasting → short term, high investment (milk content)

Foraging cycle → long term/low investment (milk content)

Aquatic nurses → add fat content to their milk gradually over time

15. Describe the foraging constraints on aquatic nursers and how they are dealt with (options)

Foraging Constraints on Aquatic Nursers

Options (Odontocete moms) : 

1. Temporary separations

   1. Baby is vulnerable when they are not with mom

   2. Shorter foraging bouts to lessen how long calf is unattended

2. Shift in maternal prey preferences

   1. Change diet while nursing

      1. Flying fish to stay at surface with calf, squids when foraging alone

      2. Enough nutrition to get them by without having to leave calf for long periods

3. Matrilineal groups with communal care 

   1. “It takes a village”

   2. Live in community with female relatives so there are babysitters when mom needs to forage/feed

      1. Sperm whales : 

         1. Live in tight knit family units

         2. 1-2 females stay at surface to watch calves while others go forage

         3. Rotate turns so they don't have to sacrifice nutrition or calf care

16. Define allomaternal care and explain which types of individuals are likely to provide it

Allomaternal care : someone other than the mother is taking care of the offspring

• Helps maximize moms reproductive success because she's less likely to lose her calf

• Limited to species that have social relationships, not solitary species 

1. Who provides care?

   1. Juvenile females

      1. Males can’t lactate, so they can't provide nutritional support

      2. Juvenile females might not be lactating, but naturally males are less likely to be around 

      3. Learning to Parent Hypothesis → gaining experience for when juvenile females has her own offspring

         1. Low risk way to learn parenting skills without the risk of losing her own offspring 

         2. Not always clear how that benefits mom and calf

         3. Overall it's still better to leave your calf with someone, even if the female is a juvenile 

            1. Young females have affinity for babies

   2. Adult females (presumably a mom herself)

      1. Most likely providing a greater benefit to the calf and mom

         1. Inclusive Fitness (direct + indirect fitness)

         2. Matrilineal social groups → all females are closely related

            1. In individuals best interest to help other females and their calves indirectly helps them pass off their genes to further generations 

            2. Also more likely to get help from others in the future when you need it

17. Explain why infanticide occurs

Infanticide : the intentional killing of young offspring by a mature animal of the same species

Functions : 

1. Advance the female’s next fecund period

2. A takeover strategy for achieving breeding space and/or acquiring a mate in the first place

3. To ensure paternal certainty

18. Differentiate among the various types of mating systems

Types of Mating Systems

1. Resource defense

   1. Males guard resources important to the female and females come to males that can provide the most for them

      1. Resources → food, breeding beach, habitat

2. Leks 

   1. Mate Choice

   2. Territorial strategy 

   3. Nothing valuable inside territory other than male itself

      1. Displays and advertises themselves in mini territories

      2. Clumps of mini territories are called leks 

      3. Females can go through and compare males to each other

3. Female Defense 

   1. Males not focused on territory, just female

   2. Mate guarding

      1. Find female they want to mate with her and stay with her until they have done the job, maybe stay after so no other male can mate with her to eliminate sperm competition

4. Scramble Competition 

   1. Just moving and trying to mate with as many females as possible before the breeding season is over 

   2. Strongest sperm wins 

Potential for male to mate with many females depends on temporal and spatial distribution of receptive females

Mating System Theory

Mating System Theory : Individuals behave to maximize reproductive success (RS) over their lifetime 

1. Sex differences → limitations on fitness 

   1. Females : limited number of eggs that they cannot use all at once

      1. Focus on resources needed to reproduce instead of mating partners

      2. Go through pregnancy/lactation and are usually sole provider for offspring

   2. Males : limitless supply of sperm

      1. Provide sperm and move on 

      2. Invest in finding as many mating partners as they can 

2. Paternal care is unlikely 

   1. Father doesn’t know 100% that any offspring is his, so he’s unlikely to invest

   2. Mom provides milk so father has no role there either

   3. In their best interest of RS to find more mates

3. Polygyny is predominate

   1. Males competing with each other for access to mating partners, hoping to fertilize more than 1 female

4. Competition for mates

   1. Contest Competition : males directly compete with each other

      1. Physical aggression/fighting 

Ex : Elephant seals

2. Scramble Competition : race to find fertile females

   1. Moving through habitats trying to find fertile female

   2. If there is another male there, not likely to engage in fight and will instead just move on

3. Mate Choice Competition : actively trying to convince females to choose a worthy mate

   1. Usually comes with some type of display 

Ex : Humpback whales singing 

4. Sperm Competition : multiple males mating with same female and strongest sperm wins

   1. Higher sperm count/faster sperm/more viable sperm is the one that wins

Ex : right whales

19. Explain the significance of temporal and spatial distribution of females to male mating strategies

Temporal Distribution 

() = # of species involved in that data set

Ex : Phocidae (12) 

Pinnipeds → most synchronous females 

• Less than 2 months for most of them 

• Median is ~ 1 month 

• Almost all females in the population are fertile at the exact same time 

  • Makes it easy for males to monopolize large groups of females at the same time

    • Think elephant seals (resource defense → controlling beach)

    • Female defense → males move

    • Resource defense → females come to males

Sperm and Orca whales both have long weaning periods and long periods where they are infertile 

• Just because a male is unsuccessful in peak breeding season, it doesn’t mean he won't be successful overall 

Mysticetes → narrow window, not as much variation as odontocetes

• Seasonal migration routes and patterns, imposes seasonal patterns on reproduction as well 

• Strong seasonal patterns leads to narrow window where female is fertile

• Most breeding occurs after that migration has occurred 

Spatial Distribution

Pinnipeds 

• Hauling out to give birth → imposes clustering on them 

• Terrestrial birthing is a driving pattern where females are at the same place at the same time in a relatively small area

• Allows males to monopolize them 

1. Otariids 

   1. Nursing strategy → foraging cycle 

   2. Coming onto breeding beach, go out to sea to feed, and then come back 

   3. Male strategy is to monopolize resources that females need (resource defense polygyny)

      1. In this case it is a safe breeding location 

      2. Shape outline = single males territory 

         1. Dots are opposing males that are trying to impose on his territory 

         2. Any females on his beach can only mate with him and he must patrol/defend those borders 

         3. Leads to territories of males that are not overlapping (on the same beach/same geographic area)

2. Phocids 

   1. Larger phocids use fasting strategy → shorter window of time where females are clustered in space and then they abruptly leave when they can no longer fast 

   2. Males are using female defense polygyny

      1. Males pick cluster of females in an area and try to stay with them 

         1. Move when the females move

         2. Male competitors are now coming in the same area because they are fighting for access to female, not defense of a territory

         3. Phocids don't move well on land/not as mobile

         4. * → comparing land-mating species 

            1. There are a few phocids that don't mate on breeding beach

            2. Use fasting strategy with a short window of time that don’t start ovulating until about when they wean the pup and return to the ocean so they won't be mating on the beach

            3. Mate in ocean instead 

            4. Some males will wait for the females that are leaving and catch them on the way out

            5. Scramble competition

20. Compare/contrast land vs. at sea mating strategies in pinnipeds

At-sea Mating Strategies

1. Walrus → leks

   1. Only reason female will come to a lek is to assess quality of mating partners (female choice) 

   2. Numbers and letters are correlated with different sounds in a vocal display that occurs above and below the ice 

      1. Kind of like humpback song

On-land Mating strategies

Pinnipeds 

• Hauling out to give birth → imposes clustering on them 

• Terrestrial birthing is driving pattern where females are at the same place at the same time in a relatively small area

• Allows males to monopolize them 

1. Otariids 

   1. Nursing strategy → foraging cycle 

   2. Coming onto breeding beach, go out to sea to feed, and then come back 

   3. Male strategy is to monopolize resources that females need (resource defense polygyny)

      1. In this case it is a safe breeding location 

      2. Shape outline = single males territory 

         1. Dots are opposing males that are trying to impose on his territory 

         2. Any females on his beach can only mate with him and he must patrol/defend those borders 

         3. Leads to territories of males that are not overlapping (on the same beach/same geographic area)

2. Phocids 

   1. Larger phocids use fasting strategy → shorter window of time where females are clustered in space and then they abruptly leave when they can no longer fast 

   2. Males are using female defense polygyny

      1. Males pick cluster of females in an area and try to stay with them 

         1. Move when the females move

         2. Male competitors are now coming in the same area because they are fighting for access to female, not defense of a territory

         3. Phocids don't move well on land/not as mobile

         4. * → comparing land-mating species 

            1. There are a few phocids that don't mate on breeding beach

            2. Use fasting strategy with a short window of time that don’t start ovulating until about when they wean the pup and return to the ocean so they won't be mating on the beach

            3. Mate in ocean instead 

            4. Some males will wait for the females that are leaving and catch them on the way out

            5. Scramble competition

(Sea Otters)

1. Otters → Resource Defense

   1. Males set up territories in kelp beds

      1. Choose a territory and adequate defend it so females can use your resources

      2. Kelp beds are imbedded in space, so those resources dont move and as long as the male otter can monopolize it, he can successfully use resource defense strategy 

         1. RDS is rarely used in marine mammals because most resources are not anchored in the ground

21. Describe how the mating strategies of fully aquatic marine mammals differ from pinnipeds

Fully Aquatic Mating Strategies 

Mysticetes

1. Humpback whales

   1. Use a variety of strategies and may be alternating throughout their life cycle

1. Leks

   1. Territories are mobile which is why there is a (?) 

   2. Advertising themselves to females with their singing

   3. Singing on breeding grounds and not feeding grounds → serves mating purpose

2. Female Defense

   1. Escorts → males “hang out” with mom and baby, forming relationship so when she becomes fertile later in breeding season he gets first dibs

   2. Not aggressive 

   3. In some ways benefitting female with protection from harassing males 

3. Contests (competition pods)

   1. Extremely aggressive and fast paced chase with active combat occurring

   2. Usually very large groups

   3. Female out front while males chase her and fight for best position to mate her 

      1. Body slams and filling ventral grooves to make themselves bigger

2. NA Right Whale

   1. Sperm competition 

   2. Record holders → largest testes size to body size ratio of any mammal ever studied 

      1. Want to flood the females reproductive tracts with your own sperm to hopefully wash out competitors 

      2. No fighting, just a lot of mating

      3. Relying on who has the strongest and healthiest sperm 

Sirenians 

• Range of strategies 

1. Scramble competition 

   1. Manatees don't live in tight-knit social groups

   2. Males go from female to female to find whos fertile at any given time

   3. Have a 6 month fertility window so they could be fertile at any point 

2. Open Contest competition (combat)

   1. Mating herd 

Odontocete Mating Strategies 

• Peak mating season with opportunity to mate outside of those windows 

• Breeding asynchronous and large ranges → difficult to monopolize large #’s of females

Bottle-nose Dolphins → Female Defense : 

1. Mate Guarding

   1. Sometimes mate-guard individually as a single male

2. Temporary Coalitions

   1. Lions have temporary alliances where males stay and work together because they are more efficient defending females from rivals together than they are separately 

   2. Not sure how they’re working out paternity 

   3. Might be inclusive fitness or the males take turns mating

3. Long-term alliances 

   1. Alliances that can last decades (what we see with bottle-nose dolphins 

Bottle-nose dolphins Male Mating Strategies

1. Long term bonds

   1. Socialize and build bonds by the time they reach sexual maturity and solidify who will be there alliance partners

   2. Variation across space and populations 

      1. Some alliances are coercive, some aggressive, some mutual between males and females

2. Some populations (very few) work together between male alliances 

   1. Second-order alliances can out-compete single alliances

   2. Will herd reproductive females and attempt to steal females from other alliances 

   3. Only seen in Shark’s Bay western Australia and here in the St. Johns river 

22. Explain the function and complexity of male bottlenose dolphin alliances

Male Mating Strategies 

1. Long term bonds

   1. Socialize and build bonds by the time they reach sexual maturity and solidify who will be there alliance partners

   2. Variation across space and populations 

      1. Some alliances are coercive, some aggressive, some mutual between males and females

2. Some populations (very few) work together between male alliances 

   1. Second-order alliances can out-compete single alliances

   2. Will herd reproductive females and attempt to steal females from other alliances 

   3. Only seen in Shark’s Bay western Australia and here in the St. Johns river 

SJR Alliance Complexity

• Have to keep track of who your friends are friends with

• High level of social complexity in bottle-nose dolphins 

• Scooter and Plateau are friends with alliances that aren’t friends with each other, which may cause conflict
  
  

FFWC Presentation

Has 6 divisions 

1. Fish and Wildlife Research Institute

2. Hunting and Game Management

3. Freshwater Fisheries Management

4. Law Enforcement

5. Habitat and Species Conservation

6. Marine Fisheries Management

Manatees 

• FWC service

• Protected by state and fed laws

• Currently listed as threatened

• Harassment is illegal → anything that changes the animals behavior including, feeding or watering 

Cetaceans 

• NOAA

• State is divided into 4 stations and 1 pathology lab 

• NE Lab is at Jacksonville Zoo 

What makes NEFL location unique?

1. Drastic tidal changes 

2. Highest rate of entanglements in florida 

   1. Dolphins

   2. Manatees 

• Some manatees get stranded in mating herds and get too much exposure to the sun

  • Can get sunburned

NA Right Whales 

• Calving season off coast of Florida

Dolphins

• Stranding and getting caught/entangled in crab pots

Hotline → 1-888-404-3922 (FWCC) hit 7 for a live dispatcher 

• Original reporting party

• Name 

Steps 

1. Verification

   1. Is it dead or alive?

   2. Photo and size estimate

   3. Recovery plan 

   4. If dead, cause of death must be determined

      1. Sometimes get summoned to fight legal cases

      2. Was it a watercraft death?

         1. Conservative on determination and might be unknown

         2. Especially for a lock death 

2. Live Marine Mammals

   1. Remain with animal and do not intervene 

   2. Report back every changes 

      1. Changes in breathing patterns

         1. Not breathing

      2. Thrashing 

3. Carcass Recovery 

   1. Trucks have EZ lift capable of lifting 2000lb

   2. Carcass trailer (must be at boat ramp)

   3. Sometimes have to tow carcasses to nearby ramp

4. Necropsies 

   1. Total length

   2. Genetics

   3. Scars

      1. Used to identify individuals 

      2. FWC and USGS database of photos 

      3. Photo ID groups visit warm water sites and springs to document animals 

      4. Share scar sketches from mortalities and rescues 

5. Rescues 

   1. Reasons for response 

      1. Boat strikes (impact/propeller)

         1. Blunt force trauma does more damage than cuts and lacerations

         2. Shock can kill

         3. Lacerations can cause gas issues/buoyancy with injuries

            1. Ribs the poke lung, lacerations that reach organs 

            2. Sinkers → injuries fill with pus or blood and cause animal to sink

               1. Harder to detect

      2. Cold stress

         1. Hypothermia

         2. nose/ margins of flipper and fluke will get lighter/bleached

         3. Ulcers from cold stress syndrome

            1. Wind burn from the air when they take a breath → can cause sores on the face

      3. Entrapment 

         1. Animals stuck in culvers

            1. In high waters, animals get stuck in places they usually can't get to and get stranded when water recedes

      4. Entanglement 

      5. Red tide

         1. Can paralyze manatees and they are not able to breathe 

         2. Help lift head above water to allow the manatee to breathe 

         3. Get 24hr monitoring in shallow water

      6. Calf by itself

Manatee Rescues

• Most are land based but more difficult in NE region

• Can use hoop nets

  • Lethargic kids

  • Smaller individuals 

  • No boat access

• Land based net set

  • Safest option

  • Manatee must be close to shore

  • Shoreline is accessible 

• Open water net set 

  • Used when :

    •  manatee is very active

    • Not near land

    • In deep water

‘Safety Concerns

• Only attempt rescue if it is in life threatening danger

• People get hurt

• Animals get hurt 

• Manatees are powerful and can cause serious injuries, especially when they thrash or are in pain 

  • People are usually injured when the manatee is “shrimping”

• Boats have been sunk 

Transport 

• Box truck modified for manatee transport 

• Equipped with pools for smaller/baby manatees

• Keep animal damp

• Surrounded by foam pads to help stabilize

• Help stimulate breath 

• Stay silent during transport to reduced stress

• Thermal blankets for cold animals 

Critical Care Facilities 

• Jax Zoo

• Tampa Zoo

• Seaworld in Orlando

“It takes a village”

Manatee Rescue and Rehabilitation Partnership (MRP) : a cooperative group that monitors the health and survival of rehabilitated and released manatees

• Takes collaboration 

Goal : 

• Release every manatee back into the wild 

• Manatees must be a certain age, length, and be released at a certain time of the year before they can be released 

  • Go to secondary care facilities to ease burden of critical care facilities 

  • Some younger ones get freeze branded for monitoring and identification 

  • Tagging efforts to make sure that the animal understands migration and seasonal patterns with health assessments every quarter

  • Tagged manatees help provide location, health assessments, and movement patterns for potential rescue and rehabilitation efforts 

Nearest Warm water sites

• Freshwater Springs (Blue Springs State Park)

• Cape canaveral 

Manatee Mating Herds

• Female beaches herself to get a break from harassment of males 

  • Sometimes people will push female back into water when she's exhausted and they end up drowning 

Ways to help

• Obey regulations

• Look for visual cues that animals are present 

• Wear polarized glasses

  • Remove glare from surface and are able to see in the water better

• Dispose of litter properly/recycle 

Atlantic Coast 2020 - Ongoing Manatee Starvation Unusual Mortality Event (UME)

• Indian River Lagoon

• Blue-green algae bloom that kills plant life and caused starvation in manatees 

• Brevard Country has the highest carcass load

• Manatees may be emaciated

• Sideways swimming manatees are typically

• Distressed manatees may be found grounded or beached

• UME manatees are typically thin or emaciated with outlines of the skull visible 

  • Outline of ribs and vertebrae 

  • Skin flaps

  • Being called in as carrcasses even though they were still alive → in such bad conditions 

• Haven't seen animals as emaciated this year and are seeing more babies 

NA Right Whales

• One of the most endangered whale species in the US

  • Population est. ~360 individuals

• Population declining fast → more deaths than births in the last 3 years

  • Only ~1/3rd of RW deaths are documented

• No dorsal fin 

• Slender tails with paddle-like flippers and v-shaped bow

Habitats 

• Migrate from New England to Canada (south) in the winter

• SE US is the only known calving ground for them

Aerial Surveys

• Aerial surveys flown in transects to determine population

  • Sends alerts when spotted to vessels in the area to document if the RW has not been previously genetically sampled (biopsy)

  • Right Whale genetic sampling from boats

• Will get a genetic sample from calf if they don't already have one

• Specially modified arrow tip with go through epidermis and blubber layer

  • For population surveys and research

• Photo Identified by splotches on head (sciamids?)

• Leading cause of death (because of surface feeding method)

  • Entanglements

    • Mainly fishing gear up in canada

      • Trying to create a ropeless fishery 

    • Creating alerts that tell vessels to reduce speed, avoid area, don't get in their way

  • Boat strikes

Entanglements 

• Can be on face or appendages

• Energy demanding 

• Can cause a slow, painful death

Disentanglement Efforts

• Human deaths have happened

• Use of specialized tools to help untangle net

• Can take days to recruit crew, attach a satellite buoy to keep track of whale